JEE Main Physics question
Ten litre of water per second is lifted from a well through 20 m and delivered with a velocity of 10 ms⁻¹, then the power of the motor is
Answer: (B)
Solution
Mass flow rate = 10 kg/s. Power = [mgh + ½mv²]/t = (10)(10)(20) + ½(10)(10²) = 2000+500 = 2500 W = 2.5 kW.