Question

two kids standing on different floors of an apartment block drop balls from the balconies . the second kid standing at a lower level drops ball after 2 seconds the first kid does .both the ball reach the ground simultaneously 5 seconds from the time the first ball was dropped . what is the difference between the height of the two balconies

Answer 1

In one second ball travels 10 m due to gravity.
The second ball is dropped 2 secs later the first one.
Thus the difference between the balconies = 10 * 2 = 20.