1) The diagram shows a situation just before a head-on collision. A lorry of mass 20 000 kg is travelling at 20.0 m s–1 towards a car of mass 900 kg travelling at 30.0 m s–1 towards the lorry.

What is the magnitude of the total momentum?

2) The diagram shows a cannon ball fired from cannon.

The mass of the cannon is 1000 kg and the mass of the cannon ball is 10 kg. The recoil velocity of the cannon is 5.0 m s^–1 horizontally. What is the horizontal velocity of the cannon ball?

3) Two similar spheres, each of mass m and travelling with speed v, are moving towards each other.

The spheres have a head-on elastic collision. Which statement is correct?

4) What is the magnitude of the momentum of an oil tanker of mass 50,000 tonnes travelling with a speed of 50 m s^-1?

5) A trolley X of total mass 0.50 kg and speed 6.0 m s⁻¹ approaches, head-on, another trolley Y of total mass 0.60 kg and speed 5.0 m s⁻¹ moving in the same direction along a level track. The collision is elastic with each trolley having a magnet with the like poles facing each other as shown below.

At some instant during the collision, X is at rest. The speed of Y then is