Question: A force $F=a+b x$ acts on a particle in the $x$-direction, where $a$ and $b$ are constants. Find the work done by this force during a displacement from $x=0$ to $x=d$.
Solution:
Work done, $W={ }_{0}^{d d}$
$F d x(F=a+b x)$
$W=\left(a+\frac{1}{2} b d\right) d$
