151. A turbine develops 10000 kW under a head of 25 metres at 135 r.p.m. Its specific speed is
152. The power of a centrifugal pump working under constant head and discharge increases with the speed.
153. Which of the following pump is successfully used for lifting water to the turbines?
154. Which of the following is not a reaction turbine?
155. A jet of water is striking at the centre of a curved vane moving with a uniform velocity in the direction of jet. For the maximum efficiency, the vane velocity is __________ of the jet velocity
156. The width of the bucket for a Pelton wheel is generally __________ the diameter of jet.
157. Choose the odd one out?
158. For 450 m head of water, __________ shallbeused.
159. The action of a centrifugal pump is that of a reversed reaction turbine.
160. The centrifugal pump preferred for a specific speed between 80 to 160 r.p.m. is
161. The speed ratio in case of Francis turbine varies from
162. A Kaplan turbine is preferred for a specific speed of 300 to 1000 r.p.m.
163. Power required to drive a centrifugal pump is directly proportional to __________ of its impeller.
164. The mechanical efficiency of an impulse turbine is
165. The overshot water wheels are those in which the wheel runs entirely by the __________ of water.
166. In a Kaplan turbine runner, the number of blades are generally between
167. If Hg is the gross or total head and hf is the head lost due to friction, then net or effective head (H) is given by