Answer:
Explanation:
When the diver stands on the platform, at 20 m above the surface of the water, he has some gravitational potential energy, which is given as
E =mgh
where m is the man's mass, g is the gravitational acceleration and h is the height above the water. The moment he jumps, the gravitational potential energy starts decreasing, because its height h above the water decreases as well, and he acquires kinetic energy, which is given as
K.E = 1/2mv^2
where v is the velocity of the diver, which is increasing. When he touches the water, all the initial gravitational potential energy has been converted into kinetic energy.
