Kinetic energy test with answers for grade 7 science (free PDF download)

Question 1 Types of energy (2 marks)

1. State the type of energy of a speeding train. (1 mark)
2. State the type of energy of a ball held at the top of a tower. (1 mark)

Question 2 A football in flight (3 marks)

A football of mass 0.45 kg moves at 12 m/s.

1. Write the formula for kinetic energy. (1 mark)
2. Calculate the kinetic energy of the football. (2 marks)

Question 3 Pot on a shelf (3 marks)

A pot of mass 4.0 kg stands on a shelf 2.5 m above the floor (g = 9.8 N/kg).

1. Calculate its gravitational potential energy. (2 marks)
2. State its gravitational potential energy if the shelf is moved to twice the height. (1 mark)

Question 4 Speed and energy (2 marks)

Explain why a car travelling at 30 m/s has much more than twice the kinetic energy of the same car at 15 m/s.

Question 5 Pendulum (3 marks)

A pendulum bob swings between A and C and passes through B, the lowest point.

1. State where the bob has maximum kinetic energy. (1 mark)
2. State the kinetic energy of the bob at A. (1 mark)
3. Explain why the swings gradually get smaller. (1 mark)

Question 6 Diving board (3 marks)

A diver of mass 50 kg stands on a board 5.0 m above the water (g = 9.8 N/kg).

1. Calculate the gravitational potential energy of the diver. (2 marks)
2. State the kinetic energy at the moment the diver reaches the water, ignoring air resistance. (1 mark)

Question 7 Mass or height? (2 marks)

Aarav says that a 1 kg ball held 2 m high has less energy than a 2 kg ball held 1 m high. Decide whether he is right and show why.

Question 8 Rolling coaster (2 marks)

A roller coaster is not given extra energy after it leaves the first hill. Explain why the second hill cannot be higher than the first.