9709 P4 - Jun 2008 - Q6
3617
A particle P of mass 0.6 kg is projected vertically upwards with speed 5.2 m/s-1 from a point O which is 6.2 m above the ground. Air resistance acts on P so that its deceleration is 10.4 m/s-2 when P is moving upwards, and its acceleration is 9.6 m/s-2 when P is moving downwards. Find
- the greatest height above the ground reached by P,
- the speed with which P reaches the ground,
- the total work done on P by the air resistance.
