An object of mass, m is moving with a constant velocity v. How much work should be done on the object in order to bring the object to rest?

Answer

Hence, the work done in order to bring the object to rest is `(1)/(2)mv^(2)`, which is done by resistive force not by applied force.

Explanation

The mass of the object = m, its initial velocity = v, final velocity = 0.
Work done on the object
= Change in kinetic energy of the object.
= Final K.E. - Initial K.E.
`=(1)/(2)m(0)^(2)-(1)/(2)mv^(2)`
`=-(1)/(2)mv^(2)`