Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A quantity with magnitude only is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: A quantity with magnitude only is a. Circle that word — that is the missing variable.
Find
We are required to find: A quantity with magnitude only is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Scalars: mass, time, speed, energy, distance. Then substitute the given, one line at a time, to get A quantity with magnitude only is a.
In other words — as if you have never seen this before
Scalars: mass, time, speed, energy, distance. Vectors need direction too.
2. What do we already know?
Definition. No numbers.
3. Which method — and why this one?
Scalars: mass, time, speed, energy, distance. Vectors need direction too.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: A quantity with magnitude only is a. Circle that word — that is the missing variable.
Find: We are required to find: A quantity with magnitude only is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Scalars: mass, time, speed, energy, distance. Then substitute the given, one line at a time, to get A quantity with magnitude only is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Definition. No numbers.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Scalars: mass, time, speed, energy, distance. Vectors need direction too.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Define
Magnitude only → scalar. Magnitude and direction → vector.
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
scalar
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
scalar
Copy onto your answer sheet — in this order
Answer: scalar
6. Check it like a marker
Speed is scalar, velocity is vector. Distance scalar, displacement vector.
7. A trap first-timers fall into
Resultant is the vector sum, not a type of quantity.
1.2 · 10 Marks
Ohm’s law is
Notes: Law question. Quote the formula sheet form.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Ohm’s law is
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Ohm’s law is. Circle that word — that is the missing variable.
Find
We are required to find: Ohm’s law is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write V = IR with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Ohm’s law is.
In other words — as if you have never seen this before
V=IR.
2. What do we already know?
Law question. Quote the formula sheet form.
3. Which method — and why this one?
V=IR.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Ohm’s law is. Circle that word — that is the missing variable.
Find: We are required to find: Ohm’s law is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: Write V = IR with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Ohm’s law is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Law question. Quote the formula sheet form.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
V=IR.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Write Ohm
Potential difference = current × resistance.
V=IR
Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
V=IR
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
V=IR
Copy onto your answer sheet — in this order
Formula: V=IR
Answer: V=IR
6. Check it like a marker
A×Ω=V. Units hold.
7. A trap first-timers fall into
P = IV is power. Q = It is charge. F = ma is Newton II.
2.1 · 10 Marks
Like magnetic poles
Notes: Two north poles, or two south poles.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Like magnetic poles
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Like magnetic poles. Circle that word — that is the missing variable.
Find
We are required to find: Like magnetic poles. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Like poles repel, unlike attract. Then substitute the given, one line at a time, to get Like magnetic poles.
In other words — as if you have never seen this before
Like poles repel, unlike attract. Same as charges.
2. What do we already know?
Two north poles, or two south poles.
3. Which method — and why this one?
Like poles repel, unlike attract. Same as charges.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Like magnetic poles. Circle that word — that is the missing variable.
Find: We are required to find: Like magnetic poles. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Like poles repel, unlike attract. Then substitute the given, one line at a time, to get Like magnetic poles.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Two north poles, or two south poles.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Like poles repel, unlike attract. Same as charges.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
State the rule
N-N or S-S: repel. N-S: attract.
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
repel
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
repel
Copy onto your answer sheet — in this order
Answer: repel
6. Check it like a marker
A compass needle’s north is attracted to the Earth’s geographic north because that is a magnetic south.
7. A trap first-timers fall into
Do not confuse with gravity — mass always attracts.
2.2 · 12 Marks · Geometrical optics
Light in vacuum travels at
Geometrical optics
Formulas
i=r
Angle of incidence = angle of reflection
Notes: Speed of electromagnetic waves in vacuum, c.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Light in vacuum travels at
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Light in vacuum travels at. Circle that word — that is the missing variable.
Find
We are required to find: Light in vacuum travels at. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write c = 3.0×10⁸ m·s⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Light in vacuum travels at.
In other words — as if you have never seen this before
c = 3.0×10⁸ m·s⁻¹. Sound in air is ~340 m·s⁻¹ — a different number.
2. What do we already know?
Speed of electromagnetic waves in vacuum, c.
3. Which method — and why this one?
c = 3.0×10⁸ m·s⁻¹. Sound in air is ~340 m·s⁻¹ — a different number.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Light in vacuum travels at. Circle that word — that is the missing variable.
Find: We are required to find: Light in vacuum travels at. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: Write c = 3.0×10⁸ m·s⁻¹ with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Light in vacuum travels at.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Speed of electromagnetic waves in vacuum, c.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
c = 3.0×10⁸ m·s⁻¹. Sound in air is ~340 m·s⁻¹ — a different number.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Quote c
c=3.0×10⁸ m·s⁻¹.
c=3.0×10⁸ m·s⁻¹
Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
3.0×10⁸ m·s⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
3.0×10⁸ m·s⁻¹
Copy onto your answer sheet — in this order
Formula: c=3.0×10⁸ m·s⁻¹
Answer: 3.0×10⁸ m·s⁻¹
6. Check it like a marker
3.0×10⁶ would be a thousand times too slow. 340 m·s⁻¹ is sound.
7. A trap first-timers fall into
Do not pick the speed of sound. Light is almost a million times faster.
5 · 3 Marks
Gaining 2×10¹² electrons gives charge (e=1.6×10⁻¹⁹ C)
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Gaining 2×10¹² electrons gives charge (e=1.6×10⁻¹⁹ C)
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 · 10¹² · 1.6 · 10⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: 6×10⁻¹⁹ C). Circle that word — that is the missing variable.
Find
We are required to find: 6×10⁻¹⁹ C). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Q = n(−e) = −3. Then substitute the given, one line at a time, to get 6×10⁻¹⁹ C).
In other words — as if you have never seen this before
Q=n(−e)=−3.2×10⁻⁷ C.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 2 · 10¹² · 1.6 · 10⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
Q=n(−e)=−3.2×10⁻⁷ C.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 2 · 10¹² · 1.6 · 10⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 6×10⁻¹⁹ C). Circle that word — that is the missing variable.
Find: We are required to find: 6×10⁻¹⁹ C). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Q = n(−e) = −3. Then substitute the given, one line at a time, to get 6×10⁻¹⁹ C).
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 2 · 10¹² · 1.6 · 10⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Q=n(−e)=−3.2×10⁻⁷ C.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
Q=n(−e)=−3.2×10⁻⁷ C.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
−3.2×10⁻⁷ C
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
−3.2×10⁻⁷ C
Copy onto your answer sheet — in this order
Answer: −3.2×10⁻⁷ C
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
6 · 2 Marks
f=50 Hz, λ=4 m. Wave speed?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f = 50 Hz, λ = 4 m. Wave speed?
Before any working — hunt first
Given
Numbers and units already in the sentence: 50 Hz · 4 m. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Wave speed. Circle that word — that is the missing variable.
Find
We are required to find: Wave speed. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: v = fλ = 200 m·s⁻¹. Then substitute the given, one line at a time, to get Wave speed.
In other words — as if you have never seen this before
v=fλ=200 m·s⁻¹.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 50 Hz · 4 m. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
v=fλ=200 m·s⁻¹.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 50 Hz · 4 m. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Wave speed. Circle that word — that is the missing variable.
Find: We are required to find: Wave speed. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: v = fλ = 200 m·s⁻¹. Then substitute the given, one line at a time, to get Wave speed.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 50 Hz · 4 m. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
v=fλ=200 m·s⁻¹.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
v=fλ=200 m·s⁻¹.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
200 m·s⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
200 m·s⁻¹
Copy onto your answer sheet — in this order
Answer: 200 m·s⁻¹
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
7 · 4 Marks · Mechanical energy
Photon energy increases if
Mechanical energy
Formulas
Ek=½ m v²
Kinetic energy
Ep=m g h
Gravitational potential
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Photon energy increases if
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Photon energy increases if. Circle that word — that is the missing variable.
Find
We are required to find: Photon energy increases if. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: E=hf. Then substitute the given, one line at a time, to get Photon energy increases if.
In other words — as if you have never seen this before
E=hf.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
E=hf.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Photon energy increases if. Circle that word — that is the missing variable.
Find: We are required to find: Photon energy increases if. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: E=hf. Then substitute the given, one line at a time, to get Photon energy increases if.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
E=hf.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
E=hf.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
frequency increases
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
frequency increases
Copy onto your answer sheet — in this order
Answer: frequency increases
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
8 · 4 Marks
6 Ω and 3 Ω in parallel. Equivalent resistance?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 6 Ω and 3 Ω in parallel. Equivalent resistance?
Before any working — hunt first
Given
Numbers and units already in the sentence: 6 Ω · 3 Ω. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Equivalent resistance. Circle that word — that is the missing variable.
Find
We are required to find: Equivalent resistance. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 1R=16 + 13=12, R = 2 Ω. Then substitute the given, one line at a time, to get Equivalent resistance.
In other words — as if you have never seen this before
1R=16+13=12, R=2 Ω.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 6 Ω · 3 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
1R=16+13=12, R=2 Ω.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 6 Ω · 3 Ω. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Equivalent resistance. Circle that word — that is the missing variable.
Find: We are required to find: Equivalent resistance. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 1R=16 + 13=12, R = 2 Ω. Then substitute the given, one line at a time, to get Equivalent resistance.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 6 Ω · 3 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
1R=16+13=12, R=2 Ω.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
1R=16+13=12, R=2 Ω.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
2 Ω
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
2 Ω
Copy onto your answer sheet — in this order
Answer: 2 Ω
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
9 · 2 Marks
P=IV. 12 V, 2 A. Power=
Notes: V=12 V, I=2 A. Unknown: P.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: P = IV. 12 V, 2 A. Power =
Before any working — hunt first
Given
Numbers and units already in the sentence: 12 V · 2 A. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Power =. Circle that word — that is the missing variable.
Find
We are required to find: Power =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write P = IV with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Power =.
In other words — as if you have never seen this before
P=IV.
2. What do we already know?
V=12 V, I=2 A. Unknown: P.
3. Which method — and why this one?
P=IV.
4. Step-by-step working
01 / 05
Write P = IV
Power is current times potential difference.
P=IV
Why this step: Write the formula before numbers. The memo awards a method mark for the law even if a digit slips later.
02 / 05
Multiply
P=12×2=24 W.
P=24 W
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
03 / 05
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
04 / 05
Step F — Box the answer with its unit
24 W
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
05 / 05
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
24 W
Copy onto your answer sheet — in this order
Formula: P=IV
Answer: 24 W
6. Check it like a marker
Watt=Js=A·V. Units hold.
7. A trap first-timers fall into
Do not add 12+2. Do not divide 122.
10 · 2 Marks
2 Ω and 2 Ω in series. R_total =
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 2 Ω and 2 Ω in series. R_total =
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 Ω · 2 Ω. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: R_total =. Circle that word — that is the missing variable.
Find
We are required to find: R_total =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 4 Ω. Then substitute the given, one line at a time, to get R_total =.
In other words — as if you have never seen this before
4 Ω
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 2 Ω · 2 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
4 Ω
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 2 Ω · 2 Ω. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: R_total =. Circle that word — that is the missing variable.
Find: We are required to find: R_total =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 4 Ω. Then substitute the given, one line at a time, to get R_total =.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 2 Ω · 2 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
4 Ω
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Series add.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
4 Ω
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
4 Ω
Copy onto your answer sheet — in this order
Answer: 4 Ω
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
11 · 2 Marks
From rest a=5 m·s⁻² for 3 s. Δx=
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: From rest a=5 m·s⁻² for 3 s. Δx=
Before any working — hunt first
Given
Numbers and units already in the sentence: 5 m·s⁻² · 3 s. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Δx=. Circle that word — that is the missing variable.
Find
We are required to find: Δx=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 22. Then substitute the given, one line at a time, to get Δx=.
In other words — as if you have never seen this before
22.5 m
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 5 m·s⁻² · 3 s. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
22.5 m
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 5 m·s⁻² · 3 s. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Δx=. Circle that word — that is the missing variable.
Find: We are required to find: Δx=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 22. Then substitute the given, one line at a time, to get Δx=.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 5 m·s⁻² · 3 s. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
22.5 m
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
½at²=½×5×9=22.5.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
22.5 m
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
22.5 m
Copy onto your answer sheet — in this order
Answer: 22.5 m
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
12 · 2 Marks
From rest, a = 2 m·s⁻² for 5 s. Distance?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: From rest, a = 2 m·s⁻² for 5 s. Distance?
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 m·s⁻² · 5 s. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Distance. Circle that word — that is the missing variable.
Find
We are required to find: Distance. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Δx = ½at² = ½×2×25 = 25 m. Then substitute the given, one line at a time, to get Distance.
In other words — as if you have never seen this before
Δx=½at²=½×2×25=25 m.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 2 m·s⁻² · 5 s. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
Δx=½at²=½×2×25=25 m.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 2 m·s⁻² · 5 s. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Distance. Circle that word — that is the missing variable.
Find: We are required to find: Distance. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Δx = ½at² = ½×2×25 = 25 m. Then substitute the given, one line at a time, to get Distance.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 2 m·s⁻² · 5 s. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Δx=½at²=½×2×25=25 m.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
Δx=½at²=½×2×25=25 m.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
25 m
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
25 m
Copy onto your answer sheet — in this order
Answer: 25 m
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
13 · 3 Marks
Two 10 Ω in parallel. R_eq=
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Two 10 Ω in parallel. R_eq=
Before any working — hunt first
Given
Numbers and units already in the sentence: 10 Ω. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: R_eq=. Circle that word — that is the missing variable.
Find
We are required to find: R_eq=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 5 Ω. Then substitute the given, one line at a time, to get R_eq=.
In other words — as if you have never seen this before
5 Ω
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 10 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
5 Ω
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 10 Ω. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: R_eq=. Circle that word — that is the missing variable.
Find: We are required to find: R_eq=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 5 Ω. Then substitute the given, one line at a time, to get R_eq=.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 10 Ω. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
5 Ω
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Half.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
5 Ω
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
5 Ω
Copy onto your answer sheet — in this order
Answer: 5 Ω
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
14 · 2 Marks
Incident angle 40°. Reflection angle?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Incident angle 40°. Reflection angle?
Before any working — hunt first
Given
Numbers and units already in the sentence: 40°. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Reflection angle. Circle that word — that is the missing variable.
Find
We are required to find: Reflection angle. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 40°. Then substitute the given, one line at a time, to get Reflection angle.
In other words — as if you have never seen this before
40°
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 40°. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
40°
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 40°. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Reflection angle. Circle that word — that is the missing variable.
Find: We are required to find: Reflection angle. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 40°. Then substitute the given, one line at a time, to get Reflection angle.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 40°. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
40°
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
i=r.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
40°
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
40°
Copy onto your answer sheet — in this order
Answer: 40°
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
15 · 2 Marks
f=25 Hz, λ=2 m. v=
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f=25 Hz, λ=2 m. v=
Before any working — hunt first
Given
Numbers and units already in the sentence: 25 Hz · 2 m. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: v=. Circle that word — that is the missing variable.
Find
We are required to find: v=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 50 m·s⁻¹. Then substitute the given, one line at a time, to get v=.
In other words — as if you have never seen this before
50 m·s⁻¹
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 25 Hz · 2 m. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
50 m·s⁻¹
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 25 Hz · 2 m. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: v=. Circle that word — that is the missing variable.
Find: We are required to find: v=. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 50 m·s⁻¹. Then substitute the given, one line at a time, to get v=.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 25 Hz · 2 m. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
50 m·s⁻¹
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
v=fλ.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
50 m·s⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
50 m·s⁻¹
Copy onto your answer sheet — in this order
Answer: 50 m·s⁻¹
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
16 · 2 Marks
A 50 kg bag. Weight on Earth? (g = 9.8)
Notes: m=50 kg. g=9.8 m·s⁻². Unknown: W.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A 50 kg bag. Weight on Earth? (g = 9.8)
Before any working — hunt first
Given
Numbers and units already in the sentence: 50 kg · 9.8. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find
We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write W = 490 N with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives 8).
In other words — as if you have never seen this before
W = mg. Mass stays 50 kg everywhere; weight changes with g.
2. What do we already know?
m=50 kg. g=9.8 m·s⁻². Unknown: W.
3. Which method — and why this one?
W = mg. Mass stays 50 kg everywhere; weight changes with g.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 50 kg · 9.8. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find: We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: Write W = 490 N with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives 8).
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
m=50 kg. g=9.8 m·s⁻². Unknown: W.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
W = mg. Mass stays 50 kg everywhere; weight changes with g.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Write W = mg
W=50×9.8=490 N.
W=490 N
Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
490 N
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
490 N
Copy onto your answer sheet — in this order
Formula: W=490 N
Answer: 490 N
6. Check it like a marker
On the moon W would be about 80 N; m is still 50 kg.
7. A trap first-timers fall into
Writing 50 N treats mass as weight.
17 · 2 Marks · Mechanical energy
SI unit of energy is the
Mechanical energy
Formulas
Ek=½ m v²
Kinetic energy
Ep=m g h
Gravitational potential
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: SI unit of energy is the
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: SI unit of energy is the. Circle that word — that is the missing variable.
Find
We are required to find: SI unit of energy is the. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: J = N·m. Then substitute the given, one line at a time, to get SI unit of energy is the.
In other words — as if you have never seen this before
J=N·m.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
J=N·m.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: SI unit of energy is the. Circle that word — that is the missing variable.
Find: We are required to find: SI unit of energy is the. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: J = N·m. Then substitute the given, one line at a time, to get SI unit of energy is the.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
J=N·m.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
J=N·m.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
joule
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
joule
Copy onto your answer sheet — in this order
Answer: joule
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
18 · 2 Marks · Pulses & superposition
Two pulses of +4 and −4 meet. The amplitude at that instant is
Formulas
y=y₁+y₂
Principle of superposition
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Two pulses of +4 and −4 meet. The amplitude at that instant is
Before any working — hunt first
Given
Numbers and units already in the sentence: 4 and · 4 meet. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The amplitude at that instant is. Circle that word — that is the missing variable.
Find
We are required to find: The amplitude at that instant is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Destructive superposition: +4 + (−4) = 0. Then substitute the given, one line at a time, to get The amplitude at that instant is.
In other words — as if you have never seen this before
Destructive superposition: +4 + (−4) = 0.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 4 and · 4 meet. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
Destructive superposition: +4 + (−4) = 0.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 4 and · 4 meet. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The amplitude at that instant is. Circle that word — that is the missing variable.
Find: We are required to find: The amplitude at that instant is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Destructive superposition: +4 + (−4) = 0. Then substitute the given, one line at a time, to get The amplitude at that instant is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 4 and · 4 meet. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Destructive superposition: +4 + (−4) = 0.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
Destructive superposition: +4 + (−4) = 0.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
0
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
0
Copy onto your answer sheet — in this order
Answer: 0
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
19 · 2 Marks
E_k of 4 kg at 3 m·s⁻¹
Notes: m = 4 kg, v = 3 m·s⁻¹. Unknown: kinetic energy E_k.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: E_k of 4 kg at 3 m·s⁻¹
Before any working — hunt first
Given
Numbers and units already in the sentence: 4 kg · 3 m·s⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: E_k of 4 kg at 3 m·s⁻¹. Circle that word — that is the missing variable.
Find
We are required to find: E_k of 4 kg at 3 m·s⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write E_k = ½mv² = 18 J with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives E_k of 4 kg at 3 m·s⁻¹.
In other words — as if you have never seen this before
E_k = ½ m v². Square the speed first, then multiply, then halve.
2. What do we already know?
m = 4 kg, v = 3 m·s⁻¹. Unknown: kinetic energy E_k.
3. Which method — and why this one?
E_k = ½ m v². Square the speed first, then multiply, then halve.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 4 kg · 3 m·s⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: E_k of 4 kg at 3 m·s⁻¹. Circle that word — that is the missing variable.
Find: We are required to find: E_k of 4 kg at 3 m·s⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: Write E_k = ½mv² = 18 J with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives E_k of 4 kg at 3 m·s⁻¹.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
m = 4 kg, v = 3 m·s⁻¹. Unknown: kinetic energy E_k.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
E_k = ½ m v². Square the speed first, then multiply, then halve.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Square v first
v²=9. Then ½×4×9=2×9=18 J.
Ek=½mv²=18 J
Why this step: If you halve the 3 first you get the wrong road. Square, then multiply by mass, then by half.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
18 J
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
18 J
Copy onto your answer sheet — in this order
Formula: Ek=½mv²=18 J
Answer: 18 J
6. Check it like a marker
A 4 kg mass at walking-ish 3 ms should be tens of joules, not hundreds. 18 J is modest and right.
7. A trap first-timers fall into
Forgetting the half (36 J) or forgetting to square (½×4×3 = 6 J). Both are on the option list on purpose.
20 · 3 Marks
A 5 kg mass at 2 m above ground. Ep (g=9.8)
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A 5 kg mass at 2 m above ground. E_p (g=9.8)
Before any working — hunt first
Given
Numbers and units already in the sentence: 5 kg · 2 m · 9.8. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find
We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: mgh=5×9. Then substitute the given, one line at a time, to get 8).
In other words — as if you have never seen this before
mgh=5×9.8×2=98 J.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 5 kg · 2 m · 9.8. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
mgh=5×9.8×2=98 J.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 5 kg · 2 m · 9.8. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find: We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: mgh=5×9. Then substitute the given, one line at a time, to get 8).
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 5 kg · 2 m · 9.8. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
mgh=5×9.8×2=98 J.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
mgh=5×9.8×2=98 J.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
98 J
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
98 J
Copy onto your answer sheet — in this order
Answer: 98 J
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
21 · 2 Marks
Like charges
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Like charges
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Like charges. Circle that word — that is the missing variable.
Find
We are required to find: Like charges. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: repel. Then substitute the given, one line at a time, to get Like charges.
In other words — as if you have never seen this before
repel
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
repel
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Like charges. Circle that word — that is the missing variable.
Find: We are required to find: Like charges. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: repel. Then substitute the given, one line at a time, to get Like charges.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
repel
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Same sign, repel.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
repel
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
repel
Copy onto your answer sheet — in this order
Answer: repel
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
22 · 4 Marks
Snell: n₁ sin θ₁=n₂ sin θ₂. n₁=1, θ₁=30°, n₂=1.5. θ₂ ≈
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Snell: n₁ sin θ₁ = n₂ sin θ₂. n₁ = 1, θ₁ = 30°, n₂ = 1.5. θ₂ ≈
Before any working — hunt first
Given
Numbers and units already in the sentence: 1 · 30° · 1.5. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: θ₂ ≈. Circle that word — that is the missing variable.
Find
We are required to find: θ₂ ≈. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: sin θ₂ = sin301. Then substitute the given, one line at a time, to get θ₂ ≈.
In other words — as if you have never seen this before
sin θ₂=sin301.5=0.333→θ₂ ≈ 19.5°.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 1 · 30° · 1.5. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
sin θ₂=sin301.5=0.333→θ₂ ≈ 19.5°.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 1 · 30° · 1.5. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: θ₂ ≈. Circle that word — that is the missing variable.
Find: We are required to find: θ₂ ≈. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: sin θ₂ = sin301. Then substitute the given, one line at a time, to get θ₂ ≈.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 1 · 30° · 1.5. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
sin θ₂=sin301.5=0.333→θ₂ ≈ 19.5°.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
sin θ₂=sin301.5=0.333→θ₂ ≈ 19.5°.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
19.5°
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
19.5°
Copy onto your answer sheet — in this order
Answer: 19.5°
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
23 · 3 Marks
Weight of a 5 kg bag of mielies on Earth (g = 9.8 m·s⁻²)
Notes: m = 5 kg. g = 9.8 m·s⁻². Unknown: weight W.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Weight of a 5 kg bag of mielies on Earth (g = 9.8 m·s⁻²)
Before any working — hunt first
Given
Numbers and units already in the sentence: 5 kg · 9.8 m·s⁻². Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8 m·s⁻²). Circle that word — that is the missing variable.
Find
We are required to find: 8 m·s⁻²). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write W = mg with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives 8 m·s⁻²).
In other words — as if you have never seen this before
Weight is the gravitational force: W = mg. Mass is not weight.
2. What do we already know?
m = 5 kg. g = 9.8 m·s⁻². Unknown: weight W.
3. Which method — and why this one?
Weight is the gravitational force: W = mg. Mass is not weight.
4. Step-by-step working
01 / 05
Write the weight law
W = m g. Unit is newton, not kilogram.
W=mg
Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.
02 / 05
Substitute
W=5×9.8=49 N.
W=49 N
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
03 / 05
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
04 / 05
Step F — Box the answer with its unit
49 N
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
05 / 05
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
49 N
Copy onto your answer sheet — in this order
Formula: W=mg
Answer: 49 N
6. Check it like a marker
On the moon g is smaller so W would drop; m stays 5 kg.
7. A trap first-timers fall into
Do not write 5 N. That treats mass as weight. Markers circle this every year.
24 · 2 Marks
E_p of 2 kg lifted 5 m (g = 9.8)
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: E_p of 2 kg lifted 5 m (g = 9.8)
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 kg · 5 m · 9.8. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find
We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 98 J. Then substitute the given, one line at a time, to get 8).
In other words — as if you have never seen this before
98 J
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 2 kg · 5 m · 9.8. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
98 J
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 2 kg · 5 m · 9.8. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 8). Circle that word — that is the missing variable.
Find: We are required to find: 8). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 98 J. Then substitute the given, one line at a time, to get 8).
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 2 kg · 5 m · 9.8. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
98 J
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
E_p = mgh = 2 × 9.8 × 5 = 98 J. Mass, then g, then height — three numbers, one energy.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
98 J
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
98 J
Copy onto your answer sheet — in this order
Answer: 98 J
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
25 · 2 Marks
f=100 Hz, v=340 m·s⁻¹. λ=
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f = 100 Hz, v = 340 m·s⁻¹. λ =
Before any working — hunt first
Given
Numbers and units already in the sentence: 100 Hz · 340 m·s⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: λ =. Circle that word — that is the missing variable.
Find
We are required to find: λ =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 3. Then substitute the given, one line at a time, to get λ =.
In other words — as if you have never seen this before
3.4 m
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 100 Hz · 340 m·s⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
3.4 m
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 100 Hz · 340 m·s⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: λ =. Circle that word — that is the missing variable.
Find: We are required to find: λ =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 3. Then substitute the given, one line at a time, to get λ =.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 100 Hz · 340 m·s⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
3.4 m
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
λ = vf=340 / 100 = 3.4 m. Wavelength is speed divided by frequency, not multiplied.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
3.4 m
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
3.4 m
Copy onto your answer sheet — in this order
Answer: 3.4 m
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
26 · 4 Marks
On a v–t graph, area under the graph is
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: On a v–t graph, area under the graph is
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: On a v–t graph, area under the graph is. Circle that word — that is the missing variable.
Find
We are required to find: On a v–t graph, area under the graph is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Area of v–t = Δx. Then substitute the given, one line at a time, to get On a v–t graph, area under the graph is.
In other words — as if you have never seen this before
Area of v–t = Δx.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
Area of v–t = Δx.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: On a v–t graph, area under the graph is. Circle that word — that is the missing variable.
Find: We are required to find: On a v–t graph, area under the graph is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Area of v–t = Δx. Then substitute the given, one line at a time, to get On a v–t graph, area under the graph is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Area of v–t = Δx.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
Area of v–t = Δx.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
displacement
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
displacement
Copy onto your answer sheet — in this order
Answer: displacement
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
27 · 2 Marks
m=2 kg. a=3 m·s⁻². Net force F?
Notes: m=2 kg. a=3 m·s⁻². Unknown: Fnet.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: m = 2 kg. a = 3 m·s⁻². Net force F?
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 kg · 3 m·s⁻². Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Net force F. Circle that word — that is the missing variable.
Find
We are required to find: Net force F. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write F = ma with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Net force F.
In other words — as if you have never seen this before
Newton 2: F_net = ma. Mass in kg, acceleration in m·s⁻², force in N.
2. What do we already know?
m=2 kg. a=3 m·s⁻². Unknown: Fnet.
3. Which method — and why this one?
Newton 2: F_net = ma. Mass in kg, acceleration in m·s⁻², force in N.
4. Step-by-step working
01 / 05
Write Newton 2
Fnet=m a. One product, no extra 9.8 — we were given a, not g.
F=ma
Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.
02 / 05
Substitute
F=2×3=6 N.
F=6 N
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
03 / 05
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
04 / 05
Step F — Box the answer with its unit
6 N
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
05 / 05
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
6 N
Copy onto your answer sheet — in this order
Formula: F=ma
Answer: 6 N
6. Check it like a marker
a = Fm=62=3 m·s⁻². Matches the given a.
7. A trap first-timers fall into
Do not multiply by g. Weight is mg; net force is ma.
28 · 2 Marks
v=fλ. f=50 Hz, λ=2 m. v=
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: v = fλ. f = 50 Hz, λ = 2 m. v =
Before any working — hunt first
Given
Numbers and units already in the sentence: 50 Hz · 2 m. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: v =. Circle that word — that is the missing variable.
Find
We are required to find: v =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 100 m·s⁻¹. Then substitute the given, one line at a time, to get v =.
In other words — as if you have never seen this before
100 m·s⁻¹
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 50 Hz · 2 m. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
100 m·s⁻¹
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 50 Hz · 2 m. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: v =. Circle that word — that is the missing variable.
Find: We are required to find: v =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 100 m·s⁻¹. Then substitute the given, one line at a time, to get v =.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 50 Hz · 2 m. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
100 m·s⁻¹
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
v=50×2=100 m·s⁻¹.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
100 m·s⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
100 m·s⁻¹
Copy onto your answer sheet — in this order
Answer: 100 m·s⁻¹
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
29 · 2 Marks
f = 50 Hz and λ = 4 m. Wave speed =
Notes: f = 50 Hz and λ = 4 m. Wave speed =
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: f = 50 Hz and λ = 4 m. Wave speed =
Before any working — hunt first
Given
Numbers and units already in the sentence: 50 Hz · 4 m. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Wave speed =. Circle that word — that is the missing variable.
Find
We are required to find: Wave speed =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: v = fλ = 50 × 4 = 200 m·s⁻¹. Then substitute the given, one line at a time, to get Wave speed =.
In other words — as if you have never seen this before
v=fλ=50×4=200 m·s⁻¹.
2. What do we already know?
f = 50 Hz and λ = 4 m. Wave speed =
3. Which method — and why this one?
v=fλ=50×4=200 m·s⁻¹.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 50 Hz · 4 m. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Wave speed =. Circle that word — that is the missing variable.
Find: We are required to find: Wave speed =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: v = fλ = 50 × 4 = 200 m·s⁻¹. Then substitute the given, one line at a time, to get Wave speed =.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
f = 50 Hz and λ = 4 m. Wave speed =
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
v=fλ=50×4=200 m·s⁻¹.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
v=fλ=50×4=200 m·s⁻¹.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
200 m·s⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
200 m·s⁻¹
Copy onto your answer sheet — in this order
Answer: 200 m·s⁻¹
6. Check it like a marker
v=fλ=50×4=200 m·s⁻¹.
7. A trap first-timers fall into
12.5 m·s⁻¹
30 · 3 Marks
Series: 2 Ω and 6 Ω on 8 V. Current?
Notes: R1=2 Ω, R2=6 Ω series. V=8 V.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Series: 2 Ω and 6 Ω on 8 V. Current?
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 Ω · 6 Ω · 8 V. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Current. Circle that word — that is the missing variable.
Find
We are required to find: Current. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
Write R = 8 Ω with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Current.
In other words — as if you have never seen this before
Series: add resistances, then I = VRtotal.
2. What do we already know?
R1=2 Ω, R2=6 Ω series. V=8 V.
3. Which method — and why this one?
Series: add resistances, then I = VRtotal.
4. Step-by-step working
01 / 05
Add series
R=2+6=8 Ω.
R=8 Ω
Why this step: One job per line so you can find a slip, and so a marker can follow the marks.
02 / 05
Ohm
I=88=1 A.
I=1 A
Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.
03 / 05
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
04 / 05
Step F — Box the answer with its unit
1 A
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
05 / 05
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
1 A
Copy onto your answer sheet — in this order
Formula: R=8 Ω
Answer: 1 A
6. Check it like a marker
Voltage split: 2 V on 2 Ω and 6 V on 6 Ω. Adds to 8 V.
7. A trap first-timers fall into
Using only 2 Ω gives 4 A. Both resistors are in the loop.