A body of mass 0.5 kg travels on straight line with path velocity $v=\left(3 x^2+4\right) \mathrm{m}

Question

A body of mass 0.5 kg travels on straight line with path velocity $v=\left(3 x^2+4\right) \mathrm{m} / \mathrm{s}$. The net work done by the force during its displacement from $x=0$ to $x=2 \mathrm{~m}$ is

Professor PC Thomas Classes · Answer

At $x=0$, $v=4 	ext{ m/s}$. At $x=2$, $v=3(4)+4=16 	ext{ m/s}$.\ $W = \Delta K = \frac{1}{2}(0.5)(16^2 - 4^2) = 60 	ext{ J}$.