Answer
$4.5 \mathrm{ft-lb}.$
Work Step by Step
The work done in moving the object from a to b is
$$
\begin{split}
W &=\int_{a}^{b} f(x) d x \\
& \quad\left[ \text { the
work done in moving the object from} \quad x=1 \text { to } x=10 \right]\\
& =\int_{1}^{10} 5 x^{-2} d x \\
&=5\left[-x^{-1}\right]_{1}^{10} \\
&=5\left(-\frac{1}{10}+1\right) \\
&=4.5 \mathrm{ft-lb}.
\end{split}
$$
