Hydraulic Turbines and Jets MCQ

111. If the discharge Q in a pipe fitted with an endcap nozzle discharging a jet of water with velocity v and hitting normally a plate which is moving with a velocity v/2 towards the nozzle, the jet would hit the plate with a discharge

  1. 0.5 Q
  2. Q
  3. 1.5 Q
  4. 2 Q
Answer
Answer. b

112. A Pelton wheel has a mean bucket speed of 10 m/s with a jet of water flowing at the rate of 700 litre/sec under a head of 30 m. The bucket deflects the jet through an angle 160°. Theoretical velocity of jet is 24.26 m/s. Assuming the coefficient of velocity 0.98, the velocity of whirl at inlet in cm/sec is

  1. 23.77
  2. 2377
  3. 23770
  4. 237.7
Answer
Answer. b

113. The force exerted by a jet of water on a stationary curved plate in direction of jet is equal to

  1. ρAv2 (1 + sinθ)
  2. ρAv2 (1 + cosθ)
  3. ρAv2 sin2θ
  4. ρAv2
Answer
Answer. b

114. If Vw and u are the whirl and tangential velocity at the impeller, work done by the impeller per unit weight of water striking per second is

  1. Vwu/g
  2. Vwu
  3. ρQVwu
  4. ρQVwVr
Answer
Answer. a