Question

A tennis ball is hit into the wall with a speed of 26 m/s.

If it rebounds with a speed of 24 m/s, how much energy was lost in the collision?


mass of tennis ball = 0.059 kg

A) 6 joules

B) 1 joule

C) 3.0 joules

Answer 1

C) 3.0 joules

Step-by-step explanation:

The kinetic energy of the ball is given by:

`K=(1)/(2)mv^2`

where

m = 0.059 kg is the mass of the ball

v is its speed

At the beginning, v = 26 m/s, so the initial kinetic energy is

`K=(1)/(2)(0.059 kg)(26 m/s)^2=20 J`

after the rebound, v = 24 m/s, so the final kinetic energy is

`K=(1)/(2)(0.059 kg)(24 m/s)^2=17 J`

So, the energy that was lost is

`E=20 J-17 J=3 J`