Water is pumped from a lake to a storage tank 20 m above at a rate of 70 L/s while consuming 20.4 kW of electric power. Disregarding any frictional losses in the pipes and any changes in kinetic energy, determine the overall efficiency of the pump–motor unit.

A ventilation opening in a room is 2 feet by 3 feet.  Air flow out of the opening is measured at 75 feet per minute.  Calculate the CFM rate.

Question 2 A water pump driven by an 800 W electric motor is used to pump water from the ground level to a tank at the rate of 20000 L/hour. Water is being discharged into the tank at 10 meters above the ground; this is the maximum rise this pump can achieve. The water and the ambient temperatures are both 10 °C. The inlet and outlet pipe diameters for the pump are both 8 cm, respectively. Determine: (1)/ The average inlet linear flow velocity of the water; 2) Assuming the efficiency of the electric motor is 95%, calculate the efficieney-of the motor-pump unit; 3) The pressure difference between the inlet and the outlet of the pump.