Question

A tennis ball is hit into the air with a racket. When is the ball’s kinetic energy the greatest? Ignore air resistance.

when it leaves the racket
just before it reaches the ground
when it reaches its maximum height
just before it starts falling downward
when its kinetic and poetntial energy are equal

Answer 1

A

Step-by-step explanation:

Answer 2

Option (a) is correct.

The ball's kinetic energy is maximum when it leaves the racket.

Step-by-step explanation:

The kinetic energy is given by KE= 1/2 mv²

Now when the tennis ball is hit by the racket, its velocity is maximum at that time. The velocity of the ball will decrease continuously because of the gravity as the ball goes up. The velocity of the ball is zero at the highest point.

So the velocity of the tennis ball is maximum when it leaves the racket. So the kinetic energy of the tennis ball is maximum when it leaves the racket.