Question

A force was applied over a mass of 40 kg by which its velocity becomes 5 M per second from 2 m per second find the magnitude of the work done by force applied

Answer 1

We will use formula of kinetic energy

1/2mu^2(u is initial velocity) - 1/2mv^2

Putting value--

1/2×40×2m/s - 1/2×40×5m/s

40-100

-60J

Work done is negative.