Problems $4$:

Underground water is to be pumped by a $78$ percent efficient $5-$kW pump to a pool whose free surface is $30$ m above the underground water level. The diameter of the pipe is $7$ cm on the intake side and $5$ cm on the discharge side. Determine the maximum flow rate of the water and the pressure difference across the pump. Assume the elevation difference between the pump inlet and the outlet and the effect of the kinetic energy correction factors to be negligible. Determine the flowrate of water and the pressure difference across the pump if the irreversible head loss of the piping system is $4$ m