The handbrake of a stationary vehicle of mass 1.5 Tonnes fails while it is parked on a 250 slope. It rolls 20m down the slope before colliding with, and locking on to, another parked vehicle of mass 0.9 Tonnes.

a) Estimate the velocity of the two vehicles immediately after the impact.

b) Will the vehicles come to a halt at some time after the collision, or continue down the hill? Assume a coefficient of friction between the tyres and the road of

*μk*=0.8, and that the handbrake only operates on the rear wheels of the vehicle.

**could someone please explain how to solve this problem? cheers x**