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3. (a) The diameter of the discharge side of a pump is 12cm, and that of the intake pipe is 14cm as shown in Figure Q3 (a). The pressure gauge at discharge reads 260 kPa and at intake 80 kPa. If the flow rate is 45 litre per seconds of water and the pump efficiency is 75%. Calculate the power required to drive the pump. [10mks) P2 pl Q D2 Pump Di Figure Q3 (a)

(b) 100 Litre per minutes of water flows through a sudden contraction from a 3 inches to a 1 inch' type L copper tube as shown in Figure Q3(b). (1) Determine the energy loss in the copper tube Determine the difference between the pressure ahead of a sudden contraction and the pressure downstream from the contraction. (111) If the water flows through a gradual contraction (angle 120°) same size as the sudden contraction, determine the energy loss and make a comparison with energy dissipated in a sudden contraction. NOTE: 1 inch = 0.0254m [24mks] Vena contracta Flow Vi D2 Di Turbulence zones Figure Q3 (b)