3. A centrifugal pump impeller has the outer diameter of 1.2 m, rotates at 520 rpm, area of the outer periphery 0.75 m2, angle of vane at outlet 25°, and

ratio of external to internal diameter 2:1, Calculate the power. Draw velocity diagram at the inlet and outlet. (The pump discharges 2.5 m/s of water. Assume, there is a constant radial flow through the device and the flow at the inlet is radial.)