Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Energy Resources and Energy Transfers
175 practice questions
Topics covered
Practice questions
21–30 of 175
Question 21
3 marks · Easy
Answer and see the solution →A student rubs their hands together on a cold day.
(a)[1 mark]Describe the main energy transfer that occurs while rubbing hands.
(b)[1 mark]Which energy store increases as the hands become warmer?
(c)[1 mark]Explain why rubbing hands is not 100% efficient.
Question 22
1 mark · Easy
Answer and check →Which method of thermal energy transfer mostly explains why the handle of a metal spoon becomes hot when placed in hot soup?
- A.Conduction
- B.Convection
- C.Radiation
- D.Insulation
Question 23
3 marks · Easy
Answer and see the solution →Describe a simple experiment you could carry out to show that air is a poor conductor of heat. Include the setup and an observation you would make.
Question 24
3 marks · Easy
Answer and see the solution →A student is asked to explain how a woolly jumper helps to keep you warm on a cold day.
(a)[1 mark]Name the process by which heat would escape without a jumper.
(b)[1 mark]Describe how the wool reduces heat loss.
(c)[1 mark]Name another common household use of a similar insulating principle.
Question 25
1 mark · Normal
Answer and check →Which method of thermal energy transfer does NOT require particles or matter to move at all?
- A.Conduction
- B.Convection
- C.Radiation
- D.Evaporation
Question 26
3 marks · Normal
Answer and see the solution →On a clear night, the temperature inside houses often drops even when windows and doors are closed and no air escapes.
(a)[3 marks]Explain, using ideas of energy transfers, why the inside of the house cools down during a clear night.
Question 27
3 marks · Normal
Answer and see the solution →Explain why a house with thick loft insulation and double glazing loses less heat in winter, referring to conduction, convection and radiation.
(a)[3 marks]Explain how each method of heat transfer is reduced by these features.
Question 28
4 marks · Normal
Answer and see the solution →A cyclist uses an electric light powered by a small dynamo attached to the bicycle wheel. When cycling, the dynamo transfers energy from the movement of the wheel to other forms.
(a)[1 mark]Name the main useful energy output from the dynamo.
(b)[1 mark]State one form of energy that is wasted during the operation of the dynamo.
(c)[2 marks]Describe, using the idea of energy stores, how energy is transferred from the cyclist’s body to the moving bicycle and eventually produces light.
Question 29
3 marks · Normal
Answer and see the solution →A laptop charger takes in 120 kJ of electrical energy from the mains and transfers 21 kJ of that to heat, which is not useful. Calculate the efficiency of the charger, giving your answer as a percentage.
Question 30
3 marks · Normal
Answer and see the solution →A student investigates how the colour of a can affects how much heat it radiates. She heats two cans, one painted matt black and one painted shiny white, to the same temperature and then measures their temperatures as they cool.
Their results are shown in the table:
Cooling of cans with different surface colours Time (min) Matt black can (°C) Shiny white can (°C) 0 80 80 2 72 75 4 65 71 6 59 68 8 54 66 (a)[2 marks]Plot a line graph of the temperature of each can against time. Draw both lines on the same axes. Label your axes.
(b)[1 mark]State which can radiates heat faster and explain why, using the graph.