Question

You drop three different types of balls: a 0.65 kg basketball with coefficient of restitution (COR) 0.85, a 0.16 billiard ball with COR 0.80, and a 0.10 kg wooden ball with COR 0.60. You drop them all so that they hit the ground with a speed of 4.43 m/s. How much thermal energy is generated during the impact with the ground? [Enter your answers in the boxes below in the same order that the different types of balls are listed in the question.]

Answer 1

Whatever change in the kinetic energy of the ball will be, it will reflect as the thermal energy released.

Now we know that,

COR= velocity of separation/ velocity of approach

For basketball,

0.85=v/4.43

v=3.7655m/s

So change in the energy will be,

0.5*0.65(4.43²-3.7655²)

=1.77 J will be thermal energy.

Similarly we can find for, billiard ball

V=0.8*4.43

V=3.544m/s

Change in kinetic energy will be

0.565 J

Similarly for wooden ball velocity will be ,

=0.6*4.43

=2.658m/s

So change in kinetic energy will be,

0.628J