Question

Define kinetic energy. What happen to the kinetic energy of its velocity become double ?

Answer 1

The energy possessed by a body because of its motion, equal to one half the mass of the body times the square of its speed is called its kinetic energy.

$K=\frac{1}{2}m{v}^2$

When, $v=2v$,

$K^{\prime }=\frac{1}{2}m(2v{)}^2$

$K^{\prime }=4\times \frac{1}{2}m{v}^2$

$K^{\prime }=4K$

Hence, when velocity is doubled, kinetic energy becomes 4 times.