Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Energy Resources and Energy Transfers
175 practice questions
Topics covered
Practice questions
41–50 of 90 · Normal
Question 41
3 marks · Normal
Answer and see the solution →A cyclist rides up a hill at a constant speed. Explain, using ideas about energy stores and transfers, why the cyclist must keep pedalling to maintain this speed.
Question 42
3 marks · Normal
Answer and see the solution →A table shows the time taken for four students to lift identical boxes through the same vertical distance:
Student Time taken (s) Ali 10 Ben 8 Chloe 12 Dina 6 Each box requires 300 J of work to be lifted.
(a)[1 mark]Which student had the greatest power output?
(b)[2 marks]Calculate the power output for this student.
Question 43
6 marks · Normal
Answer and see the solution →A construction worker lifts a toolbox of mass 12 kg vertically upwards at a steady speed through a height of 2.5 m in 5 seconds.
(a)[2 marks]Calculate the work done by the worker in lifting the toolbox.
(b)[1 mark]State the relationship between work done and energy transferred in this process.
(c)[3 marks]Calculate the power output of the worker while lifting the box.
Question 44
5 marks · Normal
Answer and see the solution →A diver of mass 60 kg jumps from a diving board 8 m above a swimming pool. Ignore air resistance.
(a)[2 marks]Calculate the gravitational potential energy (GPE) that the diver has at the top of the jump, relative to the water.
(b)[3 marks]Assuming all of the GPE is converted to kinetic energy (KE), calculate the speed of the diver just before hitting the water.
Question 45
5 marks · Normal
Answer and see the solution →A small electric cart has a mass of 120 kg and moves at a steady speed of 5 m/s along a horizontal track for 40 m. The total frictional force opposing its motion is 90 N.
(a)[2 marks]Calculate the work done against friction as the cart moves 40 m.
(b)[2 marks]Calculate the kinetic energy of the cart as it moves.
(c)[1 mark]State whether the work done against friction is equal to, less than, or greater than the kinetic energy of the cart. Explain your answer.
Question 46
5 marks · Normal
Answer and see the solution →A 400 kg rollercoaster car starts from rest at the top of a track 15 m above the ground. The car descends to the lowest point with negligible friction. Use g = 10 N/kg.
(a)[2 marks]Calculate the gravitational potential energy of the car at the top of the track.
(b)[3 marks]Calculate the speed of the car at the lowest point, assuming all the potential energy changes to kinetic energy.
Question 47
6 marks · Normal
Answer and see the solution →A student with weight 500 N runs up a set of stairs 4 m high in 10 s.
(a)[2 marks]Calculate the work done against gravity as the student climbs the stairs.
(b)[2 marks]Calculate the student's power output while running up the stairs.
(c)[2 marks]Describe one reason why the actual useful power output of the student might be less than the calculated value.
Question 48
4 marks · Normal
Answer and see the solution →The table shows different energy resources with statements about their use in generating electricity.
(a)[1 mark]State what is meant by a non-renewable energy resource.
(b)[2 marks]Coal is one example of a fossil fuel. Describe two environmental problems caused by burning coal to generate electricity.
(c)[1 mark]Explain why coal is described as a non-renewable resource.
Question 49
4 marks · Normal
Answer and see the solution →Oil and gas are widely used fossil fuels for electricity generation.
(a)[1 mark]Describe one reason why natural gas is often chosen over coal for power stations.
(b)[1 mark]State one way in which burning fossil fuels is trying to be made less harmful to the environment.
(c)[2 marks]Suggest one reason why some countries continue to use coal despite its disadvantages.
Question 50
4 marks · Normal
Answer and see the solution →Most power stations using fossil fuels contribute to the release of greenhouse gases.
(a)[2 marks]Explain what is meant by the greenhouse effect.
(b)[1 mark]State one harmful consequence of the greenhouse effect for the planet.
(c)[1 mark]Which fossil fuel produces the least carbon dioxide for the same energy output?