A diesel engine pumps 40 kg of water in 1 second. The water comes out vertically upwards with a velo

Question

A diesel engine pumps 40 kg of water in 1 second. The water comes out vertically upwards with a velocity of $3 \mathrm{~m} / \mathrm{s}$. What is the power of the engine in kilo watt ?

Professor PC Thomas Classes · Answer

Power = rate of kinetic energy = $\frac{1}{2} \frac{dm}{dt} v^2 = \frac{1}{2} 	imes 40 	imes 3^2 = 180$ W? Wait, vertically implies $P = \frac{dm}{dt}gh + \dots$ [FLAG: check matching option B (1.2 kW)]