Water enters an axial-flow turbine rotor with an absolute velocity tangential component, \(V_{\theta}\), of \(15 \mathrm{ft} / \mathrm{s}\). The corresponding blade velocity, \(U\), is \(50 \mathrm{ft} / \mathrm{s}\). The water leaves the rotor blade row with no angular momentum. If the stagnation pressure drop across the turbine is \(12 \mathrm{psi}\), determine the hydraulic efficiency of the turbine.