Given that the position of the body in `m` is a function of time as follows : `x = 2t^(4) + 5t + 4`
The mass of the body is `2 kg` . What is the increase in its kinetic energy onesecond after the stert of motion?

Options

A. `168 J`
B. `169 J`
C. `32 J`
D. `144 J`

Explanation

`x = 2t ^(4) + 5t + 4 implies v = (dx)/(dt) = 8 t + 5`
at `t = 0, v = 5 m//s`
at` t = 1 s`, `v = 8 xx 1 + 5 = 13 m//s`
Increases in `KE = (1)/(2) m[13^(2) - 5^(2)] = 144 J`