Question

A person standing near the edge of the top of a building throws two balls A and B. The ball A is thrown vertically upward and B is thrown vertically downward with the same speed. The ball A hits the ground with a speed v_A and the ball B hits the ground with a speed v_B. We have 

(a) v_A > v_B 

(b) v_A < v_B 

(c) v_A = v_B 

(d) the relation between v_A and v_B depends on height of the building above the ground.

Answer 1

The correct answer is

(c) v_A = v_B 

Explanation:

The ball 'A' thrown vertically upward will return back to the initial point with the same thrown speed but its direction will be downwards. This return speed is exactly the same as the speed of ball 'B'. So both of them will hit the ground with equal velocity.