A ball is dropped from an elevator moving upward with acceleration 'a' by a boy standing in it. The acceleration of ball with respect to [Take upward direction positive]

A platform is moving upwards with a constant acceleration of 2 m s^-2 . At time t = 0 , a boy standing on the platform throws a ball upwards with a relative speed of 8 m s^-1 . At this instant, platform was at the height of 4 m from the ground and was moving with a speed of 2 m s^-1 . Take g = 0 m s^-2 . Find (a) when and where the ball strikes the platform. (b) the maximum height attained by the ball from the ground. ( c) the maximum distance of the ball from the platform.

A platform is moving upwards with a constant acceleration of 2 m s^-2 . At time t = 0 , a boy standing on the platform throws a ball upwards with a relative speed of 8 m s^-1 . At this instant, platform was at the height of 4 m from the ground and was moving with a speed of 2 m s^-1 . Take g = 0 m s^-2 . Find (a) when and where the ball strikes the platform. (b) the maximum height attained by the ball from the ground. ( c) the maximum distance of the ball from the platform.

A bus moves over a straight level road with a constant acceleration a. A boy in the bus drops a ball out side. The acceleration of the ball w.r.t the bus and the earth are respectively