The pump of a water distribution system is powered by a 15-kw electric motor whose efficiency is 90 percent. the water flow rate through the pump is 50 l/s. the diameters of the inlet and outlet pipes are the same, and the elevation difference across the pump is negligible. if the pressures at the inlet and outlet of the pump are measured to be 100 kpa and 300 kpa (absolute), respectively, determine the mechanical efficiency of the pump. (page 99).

Liquid flows at steady state at a rate of 2 lb/'s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. the liquid specific enthalpy at the inlet is 40.09 btu/lb and at the exit is 40.94 btub. the pump requires 3 btu/s of power to operate. if kinetic energy effects are negligible and gravitational acceleration is 32.174 tt/s, the heat transfer rate associated with this steady state process is most closely 1)-2,02 btu/s from the liquid to the surroundings 2)-3.98 btu/s from the surroundings to the liquid. 3)-4.96 btu/s from the surroundings to the liquid. 4)-1.04 btu/s from the liquid to the surroundings.