1 Calculating energy changes 1.
a
Write down the equation which links speed, kinetic energy and mass.
Maths
[1 mark] b
A car of mass 900 kg is travelling at 4 m/s.
Maths You need to learn both these equations – they may not be given to you in a question.
Calculate the amount of kinetic energy it stores.
Kinetic energy store = 2.
a
J
[2 marks]
Write down the equation which links gravitational field strength, gravitational potential energy, height and mass.
Maths
[1 mark] b
A 2.0 kg box is lifted onto a 2.0 m high shelf. By how much does its gravitational potential energy change? Gravitational field strength = 9.8 N/kg.
Change in store of gravitational potential energy = 3.
a
Maths
J
[2 marks]
A diver of mass 50 kg stands on a 5.0 m high diving board. Calculate the change in the diver’s gravitational potential energy as she falls from the board into the water. Give the unit for your answer. Gravitational field strength = 9.8 N/kg.
Change in store of gravitational potential energy = Unit b
[2 marks]
As the diver falls towards the swimming pool below, energy is transferred from a store of gravitational potential energy to a store of kinetic energy and the thermal energy store of the surrounding air.
5
Physics Booster Book.indb 5
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