Quick answer: Momentum is the product of an object's mass and its velocity, p = mv, measured in kg m/s. This Physics 9-10 test on momentum has 8 questions worth 20 marks, to do in 45 minutes: momentum basics, tennis ball and locking trolleys. The mark scheme is on a separate page; free printable PDF.
This test checks momentum, conservation in collisions and explosions, impulse and safety. Answer every question, show your working and include units. The total is 20 marks. Use g = 9.8 N/kg where needed and a calculator.
Level: Physics grades 9-10 (GCSE · IGCSE · O Level · Class 9-10) · Curriculum: HS-PS2-2, HS-PS2-3
Question 2 Tennis ball (2 marks)
A tennis ball of mass 0.058 kg travels at 45 m/s. Calculate its momentum. (2 marks)
Question 3 Locking trolleys (3 marks)
A 4.0 kg trolley moving at 3.0 m/s hits a 2.0 kg trolley at rest and they lock together. Calculate their common velocity. (3 marks)
Question 4 Rifle recoil (3 marks)
A rifle of mass 4.0 kg fires a 0.020 kg bullet at 300 m/s. Calculate the recoil velocity of the rifle. (3 marks)
Question 5 Force on a trolley (3 marks)
A constant force of 30 N acts for 0.40 s on a 6.0 kg trolley that starts at rest.
- Calculate the impulse. (1 mark)
- State the change in momentum. (1 mark)
- Calculate the final speed. (1 mark)
Question 6 Airbag (2 marks)
Explain how an airbag reduces the force on a driver in a crash. (2 marks)
Question 7 Opposite directions (3 marks)
Look at the diagram. Take right as positive.
- Calculate the total momentum before. (1 mark)
- The trolleys then lock together. Calculate their combined mass. (1 mark)
- Calculate their velocity after the collision. (1 mark)
Question 8 Catching a ball (2 marks)
Explain why a fielder pulls his hands back while catching a fast cricket ball. (2 marks)
