Question

an engine can pump 30 kilo litre of water to a vertical height of 45 metre in 10 minutes calculate work done by machines and power. if efficiency of machine is 30% then how much electrical energy is used?

Answer 1

first energy used=workdone
we will find mass of water density=M/V
1000*30m^3
30000Kg
potential e=mgh
                = 30000*9.81*45
                =13230KJ
power=workdone/time
         =13230000/(6000
         =22050Watt
Rest you can do its easy