4

# 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

A. Pelton wheel with one nozzle

4

# Which of the following pump is successfully used for lifting water from deep wells?

Centrifugal pump

Reciprocating pump

Jet pump

Air lift pump

4

# If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge

Same quantity of liquid

0.75 Q

Q/0.75

1.5 Q

4

High discharge

4

# Which place in hydraulic turbine is most susceptible for cavitations?

Inlet of draft rube

Penstock

4

# The hydraulic efficiency of an impulse turbine is the

Ratio of the actual power produced by the turbine to the energy actually supplied by the turbine

Ratio of the actual work available at the turbine to the energy imparted to the wheel

Ratio of the work done on the wheel to the energy of the jet

None of the above

4

Two jets

Two runners

Four jets

Four runners

4

# Which of the following pump is generally used to pump highly viscous fluid?

Centrifugal pump

Reciprocating pump

Air lift pump

Screw pump

4

(N√Q)/H2/3

(N√Q)/H3/4

(N√Q)/H

(N√Q)/H5/4

4

Axially, axially

4

# Slip of a reciprocating pump is negative, when

Suction pipe is short and pump is running at low speeds

Delivery pipe is long and pump is running at high speeds

Suction pipe is short and delivery pipe is long and the pump is running at low speeds

Suction pipe is long and delivery pipe is short and the pump is running at high speeds

4

10° to 15°

15° to 20°

20° to 25°

25° to 30°

4

# Francis turbine is best suited for

Medium head application from 24 to 180 m

Low head installation up to 30 m

High head installation above 180 m

4

# A hydraulic ram is a device used to

Store the energy of water

Increase the pressure of water

To lift water from deep wells

To lift small quantity of water to a greater height when a large quantity of water is available at a smaller height

4

# Francis, Kaplan and propeller turbines fall under the category of

Impulse turbines

Reaction turbines

Axial flow turbines

Mixed flow turbines

4

One-half

One-third

Two-third

Three-fourth

4

waV / 2g

waV / g

waV² / 2g

waV² / g

4

# Multistage centrifugal pumps are used to

Give high discharge

Pump viscous fluids

All of these

4

# Kinematic similarity is said to exist between the model and the prototype, if both of them

Have identical velocities

Are equal in size and shape

Are identical in shape, but differ only in size

Have identical forces

4

# 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 wheel to the velocity of jet

4

L.A.N

2 L.A.N

(L.A.N)/60

(2 L.A.N)/60

4

10 r.p.m.

20 r.p.m.

40 r.p.m.

80 r.p.m.

4

# A hydraulic press is a device used

To store pressure energy which may be supplied to a machine later on

To increase the intensity of pressure of water by means of energy available from a large quantity of water at a low pressure

To lift larger load by the application of a comparatively much smaller force

All of the above

4

# In reaction turbine, draft tube is used

To transport water downstream without eddies

To convert the kinetic energy to flow energy by a gradual expansion of the flow cross-section

For safety of turbine

To increase flow rate

4

# The centrifugal pump preferred for a specific speed between 80 to 160 r.p.m. is

Slow speed with radial flow at outlet

Medium speed with radial flow at outlet

High speed with radial flow at outlet

High speed with mixed flow at outlet

4

# According to fan laws, for the fans having constant wheel diameters, the power demand varies

Directly as fan speed

Square of fan speed

Cube of fan speed

Square root of fan speed

4

# Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between

Lift and resultant force

Drag and resultant force

Lift and tangential force

Lift and drag

4

2V/(vr - v)

2V/(vr + v)

V/(vr - v)

V/(vr + v)

4

# High specific speed of turbine implies it is

Propeller turbine

Francis turbine

Impulse turbine

None of the above

4

Strain

Pressure

Kinetic

None of these