A block of mass $m$ is pulled on a rough horizontal surface which has a friction coefficient $\mu$. A horizontal force $F$ is applied which is capable of moving the body uniformly with speed $v$. Find the work done on the block in time $t$ by

(a) weight of the block,

(b) Normal reaction by surface on the block,

(c) friction,

(d) force $F$,

Calculate the work done against gravity by a coolie in carrying a load of mass $10 \mathrm{kg}$on his head when he moves uniformly a distance of $5 \mathrm{m}$ in the (i) horizontal direction, (ii) upwards vertical direction $(\mathrm{Take} g=10 \mathrm{m} {\mathrm{s}}^{-2})$.

Adjacent figure shows the force–displacement graph of a moving body, what is the work done by this force in displacing body from $x=0 \mathrm{to} x=35 \mathrm{m}?$

A $10 \mathrm{kg}$ mass moves along $x$-axis. Its acceleration as function of its position is shown in the figure. What is the total work done on the mass by the force as the mass moves from $x=0 \mathrm{to} x=8 \mathrm{cm}?$