Two trucks \(P\) and \(Q\), of masses 18 000 kg and 16 000 kg respectively, collide while moving towards each other in a straight line. Immediately before the collision, both trucks are travelling at the same speed, \(u\) ms\(^{-1}\). Immediately after the collision, \(P\) is moving at half its original speed, its direction of motion having been reversed.
- Find, in terms of \(u\), the speed of \(Q\) immediately after the collision. \hfill [5 marks]
- State, with a reason, whether the direction of \(Q\)'s motion has been reversed. \hfill [1 mark]
- Find, in terms of \(u\), the magnitude of the impulse exerted by \(P\) on \(Q\) in the collision, stating the units of your answer. \hfill [3 marks]
The force exerted by each truck on the other in the impact has magnitude \(108000u\) N.
- Find the time for which the trucks are in contact. \hfill [3 marks]