A ball is projected vertically upward from ground level with an initial speed of 25ms−1. Assume the only acceleration acting on the ball is that due to gravity, g=9.8ms−2 directed downward.
(i) Explain, with reasons, the direction and magnitude of the acceleration experienced by the ball (a) during its upward journey, (b) at the highest point of its flight, and (c) during its downward journey back to the point of projection.
(ii) Will the time taken by the ball to rise to its maximum height be equal to the time taken to return from that height to the original level? Give a reasoned argument without performing any numerical calculation.
(iii) State whether the velocity of the ball is zero anywhere other than at the highest point. Justify your answer clearly.