AQA GCSE Combined Science: Trilogy Physics Paper 2 (Higher), 2023: Question 1

9 marks · Standard Demand difficulty · Short Answer

Identify parts of the electromagnetic spectrum, compare ultraviolet and gamma rays, explain refraction in a prism, and calculate wave frequency using v = fλ.

Practise this question

Question

The question page shows a physics item about waves and the electromagnetic spectrum. Figure 1 is a horizontal spectrum diagram with boxes labelled A, B, Infrared, Visible light, Ultraviolet, C, and Gamma rays, and the task asks the student to name A, B and C. Another part asks for one similarity and one difference between ultraviolet waves and gamma rays. Figure 2 shows white light entering a glass prism and splitting into a spectrum of colours from red to violet, with the student asked to name the process when light changes direction as it enters the prism. The final parts ask for the equation linking frequency, wavelength and wave speed, and then to calculate frequency for a wave with wavelength 5.0 × 10^-7 m and speed of light 3.0 × 10^8 m/s.
Question text

01 The Sun emits a continuous spectrum of electromagnetic waves.

Figure 1 names some of the groups of waves in the electromagnetic spectrum.

Figure 1

01.1 Name groups A, B and C in Figure 1.

[2 marks]

A

B

C

01.2 Give one similarity and one difference between the properties of ultraviolet waves and

gamma rays.

[2 marks]

Similarity

Difference

Figure 2 shows white light split into a spectrum of different colours by a glass prism.

Figure 2

01.3 Light changes direction when it enters the glass prism.

What name is given to this process?

[1 mark]

Use the Physics Equations Sheet to answer questions 01.4 and 01.5.

01.4 Write down the equation that links frequency (f), wavelength (λ) and wave speed (v).

[1 mark]

01.5 The wave in the middle of the spectrum has a wavelength of 5.0 × 10–7 m.

wave speed of light = 3.0 × 108 m/s

Calculate the frequency of the wave.

[3 marks]

Frequency = Hz

Mark scheme

Show the mark scheme The mark scheme gives the correct names for the electromagnetic spectrum gaps: A is radio waves, B is microwaves, and C is X-rays. For the comparison question, accepted similarities include same speed in a vacuum, both transfer energy, or both are transverse; accepted differences include gamma rays having a higher frequency, shorter wavelength, greater ionising power, or greater penetrating power. It states the prism change in direction is refraction, and the equation is wave speed = frequency × wavelength, or v = fλ. For the calculation, it shows rearranging to f = 3.0 × 10^8 divided by 5.0 × 10^-7, giving 6 × 10^14 Hz, with equivalent correctly rounded answers accepted.

Question 1

AO /

Question Answers Extra information Mark

Spec. Ref.

01.1 A radio waves 2 AO1

6.6.2.1

B microwaves

C X-rays

allow 1 mark if 2 correct

AO /

Spec. Ref.

01.2 Similarity AO1

6.6.2.2

any one from: 1

• same speed (in a vacuum) allow both can travel through a

• both transfer energy vacuum

• both transverse allow both are ionising

allow both can harm living tissue

allow both can be used for

medical treatment / imaging

Difference

any one from: 1

• gamma has a higher allow gamma has more energy

frequency

• gamma has a shorter

wavelength

• gamma is more ionising

• gamma is more penetrating

AO /

Spec. Ref.

01.3 refraction 1 AO1

– OMBINED SCIENCE: TRILOGY – – 6.6.2.2

AO /

Spec. Ref.

01.4 wave speed = frequency × 1 AO1

wavelength 6.6.1.2

or

v = f λ

AO /

Spec. Ref.

01.5 3.0 × 108 = f × 5.0 × 10–7 1 AO2

6.6.1.2

3.0 × 108 allow a correct rearrangement 1

f = −7 using incorrect powers of 10

5.0 × 10

14 allow a correct calculation of f 1

f = 6 × 10 (Hz)

using incorrect powers of 10

allow 6.0 × 1014 (Hz)

Total Question 1 9

How to answer it

Electromagnetic Spectrum and Light Waves

What this question tests

Naming parts of the electromagnetic spectrum, comparing ultraviolet and gamma rays, recalling refraction, using the wave equation v = f λ , and calculating frequency from wavelength and wave speed using standard form and correct units.

Overview

This is a typical GCSE Physics recall + equation question. Most marks come from knowing standard facts accurately and setting out the calculation clearly.

Total marks available: 9 marks

Part 01.1 – Naming groups in the electromagnetic spectrum

Fill in A, B and C correctly

✅ Correct answers

A = radio waves
B = microwaves
C = X-rays
2 marks total. The mark scheme allows 1 mark if 2 are correct.

💡 Key knowledge

The EM spectrum in order is:

radio waves → microwaves → infrared → visible light → ultraviolet → X-rays → gamma rays

🧠 Exam technique

  • Learn the full order of the electromagnetic spectrum.
  • Work left to right: longer wavelength to shorter wavelength.
  • If visible, ultraviolet and gamma are already given, use the order to slot the missing ones in.

❌ Common errors

  • Putting X-rays before ultraviolet.
  • Mixing up radio waves and microwaves.
  • Writing “infra-red” or “UV” is usually understood, but use the full accepted names where possible.

Part 01.2 – Similarity and difference between ultraviolet and gamma rays

One similarity and one difference needed

✅ Correct answers

Similarity: any one of these gets the mark:

  • same speed in a vacuum
  • both transfer energy
  • both are transverse waves

Difference: any one of these gets the mark:

  • gamma rays have a higher frequency
  • gamma rays have a shorter wavelength
  • gamma rays are more ionising
  • gamma rays are more penetrating
1 mark for a valid similarity + 1 mark for a valid difference.

💡 Key knowledge

  • All electromagnetic waves travel at the same speed in a vacuum: 3.0 × 10⁸ m/s .
  • All electromagnetic waves are transverse.
  • Gamma rays are further along the spectrum than ultraviolet, so gamma has higher frequency and shorter wavelength.

🧠 Exam technique

  • Give one clear similarity and one clear difference only.
  • Make sure your difference actually compares them, not just states a fact about one wave without comparison.
  • Simple answers score well here. You do not need a long explanation.

Model answer: Similarity: both are transverse waves. Difference: gamma rays have a higher frequency than ultraviolet waves.

❌ Common errors

  • Saying they have different speeds in a vacuum — they do not.
  • Giving two similarities or two differences.
  • Confusing “higher frequency” with “longer wavelength” — higher frequency means shorter wavelength.
  • Writing vague answers like “gamma rays are stronger”. That is not precise enough.

Part 01.3 – Light changing direction in a prism

Name of the process

✅ Correct answer

Refraction
1 mark

💡 Key knowledge

Refraction is the change in direction of a wave when it enters a different medium because its speed changes.

🧠 Exam technique

This is a command-word recall question. If the question asks for the name of the process, give the single scientific term.

❌ Common errors

  • Writing reflection instead of refraction.
  • Describing the process instead of naming it.

Part 01.4 – Equation linking frequency, wavelength and wave speed

Recall the wave equation

✅ Correct answer

wave speed = frequency × wavelength
v = f λ
1 mark for either form.

💡 Key knowledge

  • v = wave speed in m/s
  • f = frequency in Hz
  • λ = wavelength in m

🧠 Exam technique

Learn this exactly as it appears on the equation sheet. That makes the next calculation much easier.

❌ Common errors

  • Mixing up the symbols.
  • Writing v = f ÷ λ , which is wrong.

Part 01.5 – Calculate the frequency of the wave

Use wavelength = 5.0 × 10⁻⁷ m and wave speed = 3.0 × 10⁸ m/s

📐 Calculations

  1. Write the equation:
    v = f λ
  2. Rearrange for frequency:
    f = v / λ
  3. Substitute the values:
    f = (3.0 × 10⁸) / (5.0 × 10⁻⁷)
  4. Calculate:
    f = 6 × 10¹⁴ Hz
Mark breakdown:
  • 1 mark for substitution into the equation
  • 1 mark for correct rearrangement
  • 1 mark for the correct answer: 6 × 10¹⁴ Hz
The mark scheme also allows 6.0 × 10¹⁴ Hz .

✅ Final answer

Frequency = 6 × 10¹⁴ Hz

💡 Key knowledge

  • Visible light is in the middle of the electromagnetic spectrum.
  • As wavelength gets smaller, frequency gets bigger.
  • The answer is in hertz, Hz .

🧠 Exam technique

  • Always write the equation first — this often earns or supports a method mark.
  • Rearrange before substituting if needed.
  • Keep the powers of 10 carefully lined up.
  • Include the unit Hz .

Examiner insight: students often lost marks not because they did not know the physics, but because they mishandled standard form or forgot to rearrange correctly.

❌ Common calculation traps

  • Using f = λ / v instead of f = v / λ .
  • Dropping the negative power in 10⁻⁷ .
  • Forgetting that dividing by 10⁻⁷ makes the power go up.
  • Writing the answer with no unit.

Quick full-mark recap

✅ Must-know answers

  • A = radio waves
  • B = microwaves
  • C = X-rays
  • Similarity: same speed in a vacuum / both transverse / both transfer energy
  • Difference: gamma has higher frequency or shorter wavelength
  • Refraction
  • v = f λ
  • f = 6 × 10¹⁴ Hz

🧠 What stronger answers did well

  • Used exact scientific terms.
  • Gave one valid similarity and one valid difference, clearly separated.
  • Showed working for the frequency calculation.
  • Used standard form and correct units accurately.

Topics

Physics · P6: Waves

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Physics Paper 2 (Higher), 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.