A ball is falling freely from the height 10 m. On striking the ground its energy decreases 40 %, then how high can it jump?

Answer

`6m`

Explanation

The potential energy of the ball at the height `10m=mgh`
`=mxx10xx10`
`=(100m)J`
On striking the earth its energy decreases 40 %. So remaining energy with the ball = `60% (100m)J`
`=(60)/(100)xx(100m)J`
`=(60m)J`
Suppose, after striking the ball on the ground, it can jump at height up to h., then
`60m=mxxgxxh.`
`therefore 60=10xxh.`
`therefore h.=6m`