Hydraulic Machines MCQs Archives

31. In an outward flow reaction turbine

the water flows parallel to the axis of the wheel

the water enters at the centre of the wheel and then flows towards the outer periphery of the wheel

the water enters the wheel at the outer periphery and then flows towards the centre of the wheel

the flow of water is p

✅ The correct answer is option B.

32. Which of the following pump is successfully used for lifting water to the turbines?

Centrifugal pump

Reciprocating pump

Jet pump

Air lift pump

✅ The correct answer is option C.

33. A turbine is required to develop 1500 kW at 300 r.p.m. under a head of 150 m. Which of the following turbine should be used ?

Pelton wheel with one nozzle

Pelton wheel with two or more nozzles

Kaplan turbine

Francis turbine

✅ The correct answer is option A.

34. A hydraulic intensifier is a device used to increase the intensity of pressure of water by means of energy available from a large quantity of water at a low pressure.

Correct

Incorrect

✅ The correct answer is option A.

35. The jet ratio is defined as the ratio of the

diameter of jet to the diameter of Pelton wheel

velocity of jet to the velocity of Pelton wheel

diameter of Pelton wheel to the diameter of jet

velocity of Pelton whe

✅ The correct answer is option C.

36. The discharge through a reaction turbine __________ with the increase in unit speed.

remains same

increases

decreases

✅ The correct answer is option C.

37. A jet of water enters and leaves a fixed curved vane tangentially. The force of jet along perpendicular to the vane is zero.

TRUE

FALSE

✅ The correct answer is option B.

38. The efficiency of jet propulsion for a ship with inlet orifices at right angles to the direction of motion of ship is given by

✅ The correct answer is option A.

39. The function of guide vanes in a reaction turbine is to

allow the water to enter the runner without shock

allow the water to flow over them, without forming eddies

allow the required quantity of water to enter the turbine

all of the above

✅ The correct answer is option D.

40. 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

one-half

one-third

two-third

three-fourth

✅ The correct answer is option B.