Answer
$W=0.016Btu$
Work Step by Step
We have:
$F=\frac{Constant}{x^k}$
Integrating on both sides by $dx$ we obtain:
$W=Fx=\frac{Constant(x_{2}^{1-k}-x_{1}^{1-k})}{1-k}$
Substituting:
$W=\frac{200lbf*in^{1.4}*(7in^{1-1.4}-2in^{1-1.4})}{1-1.4}=149.35lbf*in$
$W=149.35lbf*in*\frac{1ft}{12in}*\frac{1Btu}{778.169lbf*ft}=0.016Btu$
