Question:
A man moves on a straight horizontal road with a block of mass $2 \mathrm{~kg}$ in his hand. If he covers a distance of 40 in with an acceleration of $0.5 \mathrm{~m} / \mathrm{s}^{2}$, find the work done by the man on the block during the motion.
Solution:
$F=m a$
$W=F \cdot d$
$W=1 \times 40$
$W=40 \mathrm{~J}$