Chapter 3, Problem 3.20P

The Kutta-Joukowski theorem, Equation $\left(\text{3}.\text{14}0\right)$, was derived exactly for the case of the lifting cylinder. In Section 3.16 it is stated without proof that Equation $\left(\text{3}.\text{14}0\right)$ also applies in general to a two-dimensional body of arbitrary shape. Although this general result can be proven mathematically, it also can be accepted by making a physical argument as well. Make this physical argument by drawing a closed curve around the body where the closed curve is very far away from the body, so far away that in perspective the body becomes a very small speck in the middle of the domain enclosed by the closed curve.