AQA-style topic test · Energy · Higher tier
Time allowed: 45 minutes
Total: Separate Physics 41 marks · Combined Science 34 marks (skip Question 04)
You need: a calculator, a ruler and the equation sheet.
Instructions: Answer all questions on paper. Show your working in calculations. Give answers to an appropriate number of significant figures. Open the mark schemes only when you have finished the whole test.
Question 01
A roller coaster car of mass 500 kg starts from rest at the top of a slope. The top of the slope is 20 m above the bottom.
Gravitational field strength = 9.8 N/kg
01.1 Calculate the gravitational potential energy lost by the car as it travels from the top to the bottom of the slope. [2 marks]
Mark scheme
Ep = 500 × 9.8 × 20 (1)
Ep = 98 000 J (1)
01.2 Assume all of the gravitational potential energy is transferred to the kinetic energy store of the car.
Calculate the speed of the car at the bottom of the slope. [3 marks]
Mark scheme
98 000 = 0.5 × 500 × v² (1)
v² = 392 (1)
v = 19.8 m/s (1) – allow 20 m/s
allow error carried forward from 01.1
01.3 The actual speed of the car at the bottom of the slope is 18 m/s.
Calculate the efficiency of the transfer from the gravitational potential energy store to the kinetic energy store. [3 marks]
Mark scheme
Ek = 0.5 × 500 × 18² = 81 000 J (1)
efficiency = 81 000 ÷ 98 000 (1)
efficiency = 0.83 or 83% (1) – allow 0.827
Question 01 total: 8 marks
Question 02
A toy launcher uses a spring to fire a small ball straight up. The spring has a spring constant of 40 N/m. It is compressed by 15 cm.
02.1 Calculate the elastic potential energy stored in the spring.
Use the equation: Ee = ½ k e² [2 marks]
Mark scheme
Ee = 0.5 × 40 × 0.15² (1) – extension must be in metres
Ee = 0.45 J (1)
02.2 The ball has a mass of 20 g. All of the elastic potential energy is transferred to the ball.
Calculate the maximum height the ball could reach.
Gravitational field strength = 9.8 N/kg [3 marks]
Mark scheme
20 g = 0.020 kg (1)
0.45 = 0.020 × 9.8 × h (1)
h = 2.3 m (1) – allow 2.30 m
allow error carried forward from 02.1
02.3 The equation for elastic potential energy only applies under a certain condition.
State this condition. [1 mark]
Mark scheme
the limit of proportionality is not exceeded (1)
Question 02 total: 6 marks
Question 03
A student uses a 50 W electric heater to find the specific heat capacity of a 1.0 kg metal block. After the heater has warmed up, the temperature of the block rises from 21.0 °C to 30.0 °C in 180 s.
03.1 Calculate the specific heat capacity of the metal. [4 marks]
Mark scheme
E = 50 × 180 = 9000 J (1)
Δθ = 30.0 − 21.0 = 9.0 °C (1)
9000 = 1.0 × c × 9.0 (1)
c = 1000 J/kg °C (1)
03.2 The accepted value for this metal is 900 J/kg °C.
Explain why the student’s value is higher than the accepted value. [2 marks]
Mark scheme
some energy is transferred to the surroundings / heats the heater or thermometer, not the block (1)
so the temperature rise is smaller than expected for the energy supplied, which makes the calculated value of c too large (1)
03.3 Suggest one improvement to the method. [1 mark]
Mark scheme
any one from (1):
• use more / thicker insulation around the block
• put a few drops of water (or oil) in the thermometer hole to improve thermal contact
• use a joulemeter to measure the energy supplied directly
Question 03 total: 7 marks
🔷 SEPARATE PHYSICS ONLY – Combined Science students skip Question 04
(The thermal insulation required practical is only in Separate Physics.)
Question 04
A student investigates how the number of layers of newspaper around a beaker affects how quickly hot water cools. She measures the temperature drop in 10 minutes. She repeats each test three times. Table 1 shows her results.
| Layers of newspaper | Drop 1 (°C) | Drop 2 (°C) | Drop 3 (°C) | Mean drop (°C) |
|---|---|---|---|---|
| 0 | 24.0 | 23.6 | 24.4 | 24.0 |
| 1 | 18.2 | 17.8 | 18.0 | 18.0 |
| 2 | 14.0 | 19.0 | 14.2 | X |
| 3 | 11.2 | 10.8 | 11.0 | 11.0 |
| 4 | 10.0 | 10.2 | 9.8 | 10.0 |
04.1 Identify the anomalous result in Table 1. [1 mark]
Mark scheme
19.0 °C (for 2 layers, drop 2) (1)
04.2 Calculate the mean temperature drop X for 2 layers. [1 mark]
Mark scheme
(14.0 + 14.2) ÷ 2 = 14.1 °C (1) – the anomalous result must be ignored
04.3 Describe the pattern shown by the mean results. [2 marks]
Mark scheme
as the number of layers increases, the temperature drop decreases (1)
each extra layer makes less difference / the decrease gets smaller (1)
04.4 Explain why the water should start at the same temperature in each test. [2 marks]
Mark scheme
the rate of cooling depends on the temperature difference between the water and the surroundings (1)
so it is a fair test / only the number of layers affects the result (1)
04.5 Why did the student repeat each test? [1 mark]
Mark scheme
to identify anomalous results / to check the results are repeatable / to calculate a mean (1)
Question 04 total: 7 marks
Question 05
An electric motor in a crane has an input power of 1200 W. The efficiency of the motor is 0.75.
05.1 Calculate the useful power output of the motor. [2 marks]
Mark scheme
0.75 = useful power output ÷ 1200 (1)
useful power output = 900 W (1)
05.2 The crane lifts a 45 kg load through a height of 6.0 m.
Calculate the time taken to lift the load. Give your answer to 2 significant figures.
Gravitational field strength = 9.8 N/kg [3 marks]
Mark scheme
Ep = 45 × 9.8 × 6.0 = 2646 J (1)
t = 2646 ÷ 900 (1)
t = 2.9 s (1)
allow error carried forward from 05.1
05.3 Describe two ways the efficiency of the motor could be increased. [2 marks]
Mark scheme
any two from (1 each):
• lubricate the moving parts to reduce friction
• use wires with a lower resistance to reduce heating
• reduce air resistance / streamline moving parts
Question 05 total: 7 marks
Question 06
A town needs a new supply of electricity. The council is choosing between a gas-fired power station and an offshore wind farm.
06.1 Evaluate the use of each energy resource for generating the town’s electricity. [6 marks]
Mark scheme
Level 3 (5–6 marks): a detailed evaluation of both resources, comparing advantages and disadvantages, with a reasoned conclusion.
Level 2 (3–4 marks): advantages and/or disadvantages of both resources are described, with some comparison.
Level 1 (1–2 marks): simple statements about one or both resources.
0 marks: no relevant content.
Indicative content:
Gas: reliable – can generate at any time; quick start-up to meet sudden demand; releases carbon dioxide, adding to global warming; non-renewable, so supplies will run out; ongoing fuel costs.
Wind: renewable; no carbon dioxide released when generating; no fuel costs; unreliable – depends on wind speed; high building costs; offshore turbines are harder to maintain; some people think they spoil the view.
Conclusion: e.g. wind is better for the environment, but gas (or another backup) is needed when the wind is not blowing.
Question 06 total: 6 marks
END OF TEST. Total: Separate Physics 41 marks · Combined Science 34 marks.
Next: Energy – Foundation test · Energy topic page · All topic tests
