4

Two

Four

Six

Eight

C. Six

4

# Which of the following statement is correct as regard to water wheels?

They have slow speeds

They are suitable even for low water heads

They give constant efficiency, even if the discharge is not constant

All of the above

4

24.8 r.p.m.

48.2 r.p.m

82.4 r.p.m.

248 r.p.m

4

# According to fan laws, at constant weight of air or gas, the speed, capacity and pressure vary

Directly as the air or gas density

Inversely as square root of density

Inversely as density

As square of density

4

# If the net positive suction head (NPSH) requirement for the pump is not satisfied, then

No flow will take place

Cavitation will be formed

Efficiency will be low

Excessive power will be consumed

4

4

# Slip of a reciprocating pump is defined as the

Ratio of actual discharge to the theoretical discharge

Sum of actual discharge and the theoretical discharge

Difference of theoretical discharge and the actual discharge

Product of theoretical discharge and the actual discharge

4

An axial flow

An inward flow

An outward flow

A mixed flow

4

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

Inlet of draft rube

Penstock

4

waV/2g × sinθ

waV/g × sinθ

waV²/2g × sin2θ

waV²/g × sinθ

4

# Medium specific speed of a pump implies it is

Centrifugal pump

Mixed flow pump

Axial flow pump

Any one of the above

4

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

Impulse turbines

Reaction turbines

Axial flow turbines

Mixed flow turbines

4

10 r.p.m.

20 r.p.m.

40 r.p.m.

80 r.p.m.

4

# Delivery head of a centrifugal pump is

Directly proportional to N

Inversely proportional to N

Directly proportional to N²

Inversely proportional to N²

4

# If the ratios of all the corresponding linear dimensions are equal, then the model and the prototype are said to have

Geometric similarity

Kinematic similarity

Dynamic similarity

None of these

4

# Head developed by a centrifugal pump is

Proportional to diameter of impeller

Proportional to speed of impeller

Proportional to diameter and speed of impeller

None of the above

4

Pelton wheel

Francis turbine

Kaplan turbine

None of these

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

# 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

40 %

50 %

60 %

80 %

4

# The ratio of quantity of liquid discharged per second from the pump to the quantity of liquid passing per second through the impeller is known as

Manometric efficiency

Mechanical efficiency

Overall efficiency

Volumetric efficiency

4

0.15 to 0.3

0.4 to 0.5

0.6 to 0.9

1 to 1.5

4

# The hydraulic efficiency of a reaction turbine, is the ratio of

Power produced by the turbine to the energy actually supplied by the turbine

Actual work available at the turbine to energy imparted to the wheel

Workdone on the wheel to the energy (or head of water) actually supplied to the turbine

None of the above

4

# For starting an axial flow pump, its delivery valve should be

Closed

Open

Depends on starting condition and flow desired

Could be either open or closed

4

# Which of the following pump is successfully used for lifting water to the boilers?

Centrifugal pump

Reciprocating pump

Jet pump

Airlift pump

4

L.A.N

2 L.A.N

(L.A.N)/60

(2 L.A.N)/60

4

# Low specific speed of turbine implies it is

Propeller turbine

Francis turbine

Impulse turbine

Any one of the above

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

# 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

Axially, axially