The displacement of a body of mass `2 kg` varies with time `t` as `S = t^(2) + 2t`, where `S` is in seconds. The work done by all the forces acting on the body during the time interval `t = 2s` to `t = 4s` is

Options

A. 63 J
B. 61 J
C. 62 J
D. 60 J

Answer

`(4)`

Explanation

`S = t^(2) + 2t`
`V = ds/dt = 2t + 2`
`V(t = 0 ) = 2m/s`
`V(t = 3s) = 8 m/s`
`w = 1/2m(V_(t=3)^(L) - V_(t-0)^(L))`