$3\mathrm{.}11.$ Air flows through a converging pipe section, as shown in Fig. P$3\mathrm{.}11.$ Since the centerline of

the duct is horizontal, the change in potential energy is zero. The Pitot probe at the upstream

station provides a measure of the total pressure $($or stagnation pressure$).$ The downstream

end of the U$-$tube provides a measure of the static pressure at the second station. Assum$-$

ing the density of air to be $0\mathrm{.}00238$ slug$/f{t}^3$ and neglecting the effects of viscosity, com$-$

pute the volumetric flow rate in $f\frac{t^3}{s}.$ The fluid in the manometer is unity weight oil

slug $(\frac{\text{:}}{f}{t}^3$