A boy standing on a stationary lift (open from above) throws a ball upwards with the maximum initial speed he can, equal to `49 ms^(-1)`. How much time does the ball take to return to his hands ? If the lift starts moving up with a uniform speed of `5 ms^(-1)` and the boy again throws the ball up with the maximum speed he can, how long does the ball take to return to his hands ?

Explanation

10s, 10 s