AQA GCSE Physics Physics Paper 1 (Foundation), November 2021: Question 10

9 marks · Standard Demand difficulty · Short Answer

Calculate the energy needed to increase the temperature of deuterium for nuclear fusion and explain environmental effects of fossil fuels.

Practise this question

Question

A four-part physics exam question about nuclear fusion and energy resources. Part 10.1 asks to complete sentences about nuclear fusion. Part 10.2 is a calculation of energy needed to heat deuterium using specific heat capacity. Part 10.3 asks to suggest two reasons why models were tested. Part 10.4 asks to explain one environmental effect of generating electricity using fossil fuels.
Question text

10 Energy from the Sun is released by nuclear fusion.

10.1 Complete the sentences.

[2 marks]

Nuclear fusion is the joining together of .

During nuclear fusion the total mass of the particles .

10.2 Nuclear fusion of deuterium is difficult to achieve on Earth because of the high

temperature needed.

Electricity is used to increase the temperature of 4.0 g of deuterium by 50 000 000 °C.

specific heat capacity of deuterium = 5200 J/kg °C

Calculate the energy needed to increase the temperature of the deuterium

by 50 000 000 °C.

Use the Physics Equations Sheet.

[3 marks]

39 Energy =

J

10.3 The idea of obtaining power from nuclear fusion was investigated using models.

The models were tested before starting to build the first commercial nuclear fusion

power station.

Suggest two reasons why models were tested.

[2 marks]

*38* 2

10.4 Generating electricity using nuclear fusion will have fewer environmental effects than

generating electricity using fossil fuels.

Explain one environmental effect of generating electricity using fossil fuels.

[2 marks]

Mark scheme

Show the mark scheme A mark scheme table for question 10, detailing correct answers for parts 10.1 through 10.4, including unit conversions for mass, the formula for specific heat capacity calculation yielding 1.04 x 10^9 J, valid suggestions for model testing, and environmental impacts of fossil fuels like global warming from carbon dioxide.

Question 10

AO /

Question Answers Extra information Mark

Spec. Ref.

nuclei do not accept atoms 1

10.1 AO1

4.4.4.2

decreases 1

10.2 m = 0.004 (kg) 1 AO2

4.3.2.2

E = 0.004 × 5200 × 50 000 000 allow a correct substitution of an 1 4.1.1.3

incorrectly/not converted value

of m

E = 1.04 × 109 (J) allow a correct calculation using 1

or an incorrectly/not converted

E = 1 040 000 000 (J) value of m

10.3 any two from: 2 AO3

• to make sure the fusion 4.1.3

process is possible

• to develop an understanding

of the process

• to make adaptations to the

process

• to assess the efficiency of the

process

• to make predictions

• assess safety risks

• to assess environmental

impact

• set-up cost is lower (for small

scale experiments)

allow releases greenhouse

10.4 releases carbon dioxide 1 AO1

gases

4.1.3

which causes global warming allow which causes climate 1

change

OR

releases particulates

which causes global dimming

or

which causes breathing

problems

OR

releases sulfur dioxide

which causes acid rain

OR

releases nitrogen oxides

which causes breathing

problems

or

which causes acid rain

Total 9

How to answer it

Nuclear Fusion & Energy Resources Study Guide

What this question tests

This question assesses your recall of nuclear fusion definitions and mass changes, ability to apply the specific heat capacity equation with unit conversions, reasoning skills for scientific modelling, and knowledge of the environmental impacts of fossil fuels versus nuclear power.

Question 10.1 (2 marks)

Defining Nuclear Fusion and Mass Changes

✅ Correct Answers

  • Blank 1: nuclei (do not accept atoms)
  • Blank 2: decreases

💡 Key Knowledge

  • Nuclear fusion involves small light nuclei joining together to form a heavier nucleus.
  • During this process, a small amount of mass is converted into energy (Einstein's E = mc²). Therefore, total mass decreases.

❌ Common Errors

  • Writing "atoms" instead of "nuclei" loses the first mark. Atoms contain electrons and shells which are not what fuses in the core.
  • Stating that mass "increases" or "stays the same".
Question 10.2 (3 marks)

Calculating Thermal Energy (Specific Heat Capacity)

📐 Step-by-Step Calculation

  1. Convert units for mass:
    4.0 g = 4.0 ÷ 1000 = 0.004 kg
  2. Recall the equation:
    E = m × c × ΔT
  3. Substitute values:
    E = 0.004 × 5200 × 50 000 000
  4. Calculate final answer:
    Energy = 1.04 × 10⁹ J (or 1 040 000 000 J )

🧠 Exam Technique & Mark Scheme

  • Mark 1: Correct conversion of mass to kg ( 0.004 kg ).
  • Mark 2: Correct substitution into the specific heat capacity formula.
  • Mark 3: Correct final numerical answer with correct units or standard form.
  • Note: The mark scheme allows ecf (error carried forward) if you forgot to convert grams to kilograms, so always write down your working out clearly!
Question 10.3 (2 marks)

Suggesting Reasons for Testing Models

✅ Acceptable Answers (Any Two)

  • To make sure the fusion process is possible.
  • To develop an understanding of the process.
  • To make adaptations / improvements to the process.
  • To assess the efficiency of the process.
  • To make predictions / assess safety risks / check environmental impact.
  • Set-up cost is lower for small-scale experiments.

🧠 Exam Technique

  • This is an AO3 question testing your analytical and evaluative skills regarding experimental design.
  • Keep answers concise and focused on safety, cost, feasibility, or understanding. Vague answers like "to see if it works" should be backed up with scientific context where possible, though "to make sure the process is possible" is credited.
Question 10.4 (2 marks)

Environmental Effects of Fossil Fuels

✅ Correct Explanations (Any One full link needed for 2 marks)

  • Releases carbon dioxide / greenhouse gases which causes global warming / climate change.
  • Releases particulates which causes global dimming or breathing problems.
  • Releases sulfur dioxide / nitrogen oxides which causes acid rain (or breathing problems).

❌ Common Errors & Mark Loss

  • Students often state the pollutant (e.g., "releases carbon dioxide") but fail to state the consequence ("which causes global warming").
  • To get both marks, you need the cause AND the environmental effect.

Topics

Physics · P1: Energy · P4: Atomic Structure

Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 1 (Foundation), November 2021. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.