AQA GCSE Physics Physics Paper 1 (Foundation), November 2021: Question 6
10 marks · Standard Demand difficulty · Short Answer
Analyze solar power systems on a house regarding energy resources, charge flow, efficiency, and dissipation.
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Question text
06 Figure 10 shows a house with a solar power system.
The solar cells generate electricity.
When the electricity generated by the solar cells is not needed, the energy is stored in
a large battery.
Figure 10
06.1 The solar cells on the roof of the house always face in the same direction.
Explain one disadvantage caused by the solar cells only facing in one direction.
[2 marks]
06.2 The mean current from the solar cells to the battery is 3.5 A.
Calculate the charge flow from the solar cells to the battery in 3600 seconds.
Use the equation:
charge flow = current × time
[2 marks]
Charge flow = C
06.3 Write down the equation which links efficiency, total power input and
useful power output.
[1 mark]
06.4 At one time in the day, the total power input to the solar cells was 7500 W.
The efficiency of the solar cells was 0.16
Calculate the useful power output of the solar cells.
[3 marks]
Useful power output = W
06.5 The wasted energy that is not usefully transferred by the solar cells is dissipated.
What happens to energy that has been dissipated?
[1 mark]
Tick ( ) one box.
The energy becomes less useful.
The energy is destroyed.
The energy is used to generate electricity.
06.6 Why is it unlikely that all the UK’s electricity needs could be met by
solar power systems?
[1 mark]
Tick ( ) one box.
A very large area would need to be covered with solar cells.
Solar power is a non-renewable energy resource.
The efficiency of solar cells is too high.
Mark scheme
Show the mark scheme
Question 6
AO/
Question Answers Extra information Mark
Spec. Ref
(fixed) solar cells aren’t always 1
06.1 AO3
pointed (directly) at the Sun
4.1.3
or
(fixed) solar cells don’t track the
Sun (through the sky)
(fixed) solar cells don’t (always)
allow solar cells won’t receive as 1
receive maximum intensity of
much (solar) energy
solar radiation
allow solar cells won’t generate
as much electricity
06.2 Q = 3.5 × 3600 1 AO2
4.2.1.2
Q = 12 600 (C) 1
06.3 useful power output
1 AO1
efficiency = 4.1.2.2
total power input
06.4 useful power output
1 AO2
0.16 = 4.1.2.2
7500
useful power output = 1
0.16 × 7500
useful power output = 1200 (W) 1
06.5 the energy becomes less useful 1 AO1
4.1.2.1
06.6 a very large area would need to 1 AO3
be covered with solar cells 4.1.3
Total 10
How to answer it
GCSE Physics Study Guide: Solar Power Systems
What this question tests
This question tests your understanding of renewable energy resources (solar power), application of standard physics equations (charge flow, efficiency), energy dissipation principles, and evaluation of large-scale energy generation limitations.
Disadvantages of Fixed Solar Cells
✅ Correct Answer
Fixed solar cells aren't always pointed directly at the Sun / don't track the Sun through the sky, meaning they won't receive maximum intensity of solar radiation or generate as much electricity.
🧠 Exam Technique
This is an AO3 analysis question. You must link the physical constraint (fixed direction) to the consequence (missing peak sunlight angles) to secure both marks.
Calculating Charge Flow
📐 Step-by-Step Calculation
- Identify the equation: charge flow = current × time (Q = I × t)
- Substitute values: Q = 3.5 A × 3600 s
- Calculate result: Q = 12600 C
❌ Common Errors
Students sometimes fail to convert time properly if given in minutes or hours, or forget to include standard units ( C or Coulombs ) at the end of their answer line.
Equation for Efficiency
✅ Correct Answer
efficiency = useful power output / total power input
💡 Key Knowledge
You must recall standard equations accurately. Note that energy or power units are interchangeable in the efficiency equation depending on the context given in the stem.
Calculating Useful Power Output
📐 Step-by-Step Calculation
- Rearrange the equation: useful power output = efficiency × total power input
- Substitute values: 0.16 × 7500 W
- Calculate result: 1200 W
🧠 Exam Technique
Always show your substitution clearly even if you do the final multiplication in your head. This protects your method mark if a careless arithmetic error happens.
Energy Dissipation
✅ Correct Answer
Tick the box: "The energy becomes less useful."
💡 Key Knowledge
Dissipated energy spreads out into the surroundings and is stored in less useful energy stores (such as thermal energy stores of the air). Energy is never destroyed (conservation of energy).
Limitations of Solar Power in the UK
✅ Correct Answer
Tick the box: "A very large area would need to be covered with solar cells."
❌ Common Errors
Students occasionally fall for distractors claiming solar is non-renewable. Remember that solar power is definitely renewable; the primary challenge for large-scale integration is low power density requiring vast surface areas.
Topics
Physics · P1: Energy · P2: Electricity
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.