A 0.13hp electric motor on a water well pumps water from 30.23m below the surface. The density of water is 1.0 kg/liter. How many kg of water does the motor pump in 2.20hr?
It is known that 1 hp = 746 watts, so 0.13 hp = 97 watts = 97 Joules/s The amount of work to lift 1 kg water a vertical distance = 30.23 m = mgh mgh = (1)(9.81)(30.23) = 296.6 J no. of seconds in 2.20 hr = (2.2)(3600) = 7920 s total work output of a 0.13 hp pump in 2.2 hr if 100% efficient = (7920)(97) = 768,240 J no of kg lifted by 100% efficient pump/motor in 2.2 hr = 768,240/296.6 = 2590 kg ANS
