Problem $9\mathrm{.}2$

$9\mathrm{.}2$ Fluid flows past the two$-$dimensional bar shown in Fig. P$9\mathrm{.}2.$ The pressures on the ends of the bar are as shown, and the average shear stress on the top and bottom of the bar is ${}_{\text{a}\text{v}\text{g}\text{.}\text{A}\text{s}\text{s}\text{u}\text{m}\text{e}}$ that the drag due to pressure is equal to the drag due to viscous effects. $($a$)$ Determine ${}_{\text{a}\text{v}\text{g}}$ in terms of the dynamic pressure, $\frac{U^2}{2}.$

$($b$)$ Determine the drag coefficient for this object.