The coefficient of the restitution of an object is defined as the ratio of its outgoing to incoming speed when the object collides with a rigid surface. for an object with a coefficient of 0.72, what fraction of the object's kinetic energy is lost during a single collision?

48.16 %

Explanation:

coefficient of restitution = 0.72

let the incoming speed be = u

let the outgoing speed be = v

kinetic energy = 0.5 x mass x

       0.72 =

       v = 0.72u

        therefore the outgoing kinetic energy = 0.5 x m x

        outgoing kinetic energy = 0.5 x m x

        outgoing kinetic energy = 0.5184 (0.5 x m x )

recall that 0.5 x m x is our incoming kinetic energy, therefore

outgoing kinetic energy = 0.5184 x (incoming kinetic energy)

from the above we can see that the outgoing kinetic energy is 51.84 % of the incoming kinetic energy.

The energy lost would be 100 - 51.84 = 48.16 %

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s