Question

A pump having efficiency 75% lifts 800 kg water per minute from a 14 m deep well and throws at a speed of 18 ms^-1. Find the power of the pump.

• A. 2060 W
• B. 2490 W
• C. 3218 W
• D. 1400 W

Answer 1

Answer: (B)

2490 W

Answer 2

P_eff = $\frac{dm}{dt}gh = \frac{800}{60} \times 10 \times 14$ = $\frac{5600}{3}W.$

P_app = P_eff × $\frac{4}{3} = \frac{22400}{9}$ = 2488.88 W