4

2 to 4

4 to 8

8 to 16

16 to 24

D. 16 to 24

4

# Overall efficiency of a centrifugal pump is the ratio of

Energy available at the impeller to the energy supplied to the pump by the prime mover

Actual workdone by the pump to the energy supplied to the pump by the prime mover

Energy supplied to the pump to the energy available at the impeller

Manometric head to the energy supplied by the impeller per kN of water

4

0 to 25 m

25 m to 250 m

Above 250 m

None of these

4

Volute casing

Vortex casing

Any one of these

4

4

6

8

12

4

# Axial flow pump is started with its delivery valve

Kept fully closed

Kept fully open

Irrespective of any position

Kept 50% open

4

# In a reaction turbine, the draft tube is used

To run the turbine full

To prevent air to enter the turbine

To increase the head of water by an amount equal to the height of the runner outlet above the tail race

To transport water to downstream

4

# Discharge of a centrifugal pump is

Directly proportional to diameter of its impeller

Inversely proportional to diameter of its impeller

Directly proportional to (diameter)² of its impeller

Inversely proportional to (diameter)² of its impeller

4

175.4 r.p.m.

215.5 r.p.m.

241.5 r.p.m.

275.4 r.p.m

4

# The specific speed of a turbine is the speed of an imaginary turbine, identical with the given turbine, which

Delivers unit discharge under unit head

Delivers unit discharge under unit speed

Develops unit power under unit head

Develops unit power under unit speed

4

# Which type of the pump is different from others in the same group?

Screw pump

Gear pump

Cam and piston pump

Plunger pump

4

# The speed of a turbine runner is

Directly proportional to H1/2

Inversely proportional to H1/2

Directly proportional to H3/2

Inversely proportional to H3/2

4

One-half

One-third

Two-third

Three-fourth

4

L.A.N

2 L.A.N

(L.A.N)/60

(2 L.A.N)/60

4

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

Centrifugal pump

Reciprocating pump

Air lift pump

Screw pump

4

Q/√H

Q/H

Q/H3/2

Q/H²

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

# Low specific speed of a pump implies it is

Centrifugal pump

Mixed flow pump

Axial flow pump

None of the above

4

# When a piping system is made up primarily of friction head and very little of vertical lift, then pump characteristics should be

Horizontal

Nearly horizontal

Steep

First rise and then fall

4

High discharge

4

# In a single casing, multistage pump running at constant speed, the capacity rating is to be slightly lowered. It can be done by

Designing new impeller

Trimming the impeller size to the required size by machining

Not possible

Some other alterations in the impeller

4

Product

Difference

Sum

None of these

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

# Dynamic 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

None of the above

4

# Geometric 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

N√P / H3/2

N√P / H²

N√P / H5/4

N√P / H3

4

# A Pelton wheel is

Tangential flow impulse turbine

Inward flow impulse turbine

Outward flow impulse turbine

Inward flow reaction turbine

4

# In a reciprocating pump, air vessels are used to

Smoothen the flow

4

Same

0.75 B.H.P.

B.H.P./0.75

1.5 B.H.P.

4

# The working of which of the following hydraulic units is based on Pascal's law?

Air lift pump

Jet pump

Hydraulic coupling

Hydraulic press