1. A boy standing on top of a tower throws up a ball with a velocity u. The ball reach to foot of the tower with velocity 3u. The height of the tower is:
(a) 2u^2/g
(b) u^2/g
(c) 3u^2/g
(d) 4u^2/g
2. Two cars A and B starting from rest accelerate uniformly at the same rate. However, the car B...