Question

a higher jumper jumps on to a bed of sand why

Answer 1

In a high jump athletic event, the athletes are made to fall either on a cushioned bed or sand bed. This is to increase the time of the athlete's fall to stop after making the jump. This decreases the rate of change of momentum and hence, the force. As a result, the athlete does not get injured.

Answer 2

Since sand is more elastic than soil so it would be good to jump on elastic things like if someone say jump on iron or gum...you will say gum is good....