P$2\mathrm{.}157$ The $45$ V$-$tube in Fig. P$2.157$ contains water and is open

at A and closed at $C.$ What uniform rotation rate in $r_{\frac{?}{?}}$min

about axis $AB$ will cause the pressure to be equal at

points $B$ and $C?$ For this condition, at what point in leg

$BC$ will the pressure be a minimum?

P$2\mathrm{.}157$