When a basketball is dropped it strikes the ground and bounces upwards but the height to which it rises is not the same as that from which it was dropped.
This is due to the fact that the collision between the ball and the ground is not completely elastic. Kinetic energy is conserved in only in a completely elastic collision. As the ball falls, the gravitational potential energy is gradually converted to kinetic energy. When it strikes the ground, all the potential energy has been converted to kinetic energy. If the collision were completely elastic, on bouncing up again, the kinetic energy is again converted to potential energy and the ball rises to the same height it fell from.
As the collision is an inelastic one, some of the kinetic energy is converted to heat and as it cannot be recovered it is lost.
some of the energy goes into the floor the air friction noise of vibration