4

# The power produced by the reaction turbine is ________ to the head of water.

Directly proportional

Inversely proportional

4th power

None of these

A. Directly proportional

4

# Runaway speed of a hydraulic turbine is

The speed at which turbine runner will be damaged

The speed if the turbine runner is allowed to revolve freely without load and with the wicket gates wide open

The speed corresponding to maximum overload permissible

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

4

6

8

12

4

# High specific speed of a pump implies it is

Centrifugal pump

Mixed flow pump

Axial flow pump

Any one of the above

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

# Head developed by a centrifugal pump depends on

Impeller diameter

Speed

Fluid density

Both (A) and (B) above

4

# According to fan laws, at constant pressure, the speed capacity and power vary

Directly as the air or gas density

Inversely as square root of density

Inversely as density

As square of density

4

# The cavitation in a hydraulic machine

Causes noise and vibration of various parts

Reduces the discharge of a turbine

Causes sudden drop in power output and efficiency

All of the above

4

# The cavitation in reaction turbines is avoided, to a great extent by

Installing the turbine below the tail race level

Using stainless steel runner of the turbine

Providing highly polished blades to the runner

All of the above

4

# The specific speed from 160 to 500 r.p.m. of a centrifugal pump indicates that the pump 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 axial flow at outlet

4

An axial flow

An inward flow

An outward flow

A mixed flow

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

# 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

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

# Casting of a centrifugal pump is designed so as to minimize

Friction loss

Cavitations

Loss of kinetic energy

4

# Which of the following is not a reaction turbine?

Fourneyron turbine

Journal turbine

Thomson's turbine

Pelton wheel

4

# The flow ratio of Francis turbine is defined as the ratio of the

Velocity of flow at inlet to the theoretical jet velocity

Theoretical velocity of jet to the velocity of flow at inlet

Velocity of runner at inlet to the velocity of flow at inlet

None of the above

4

# Which of the following hydraulic unit is used for transmitting increased or decreased torque to the driven shaft?

Hydraulic ram

Hydraulic intensifier

Hydraulic torque converter

Hydraulic accumulator

4

# A Pelton wheel is

Tangential flow impulse turbine

Inward flow impulse turbine

Outward flow impulse turbine

Inward flow reaction turbine

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

# Motion of a liquid in a volute casing of a centrifugal pump is an example of

Rotational flow

Forced spiral vortex flow

Spiral vortex flow

4

10° to 15°

15° to 20°

20° to 25°

25° to 30°

4

# 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 partly radial and partly axial

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

# Braking jet in an impulse turbine is used

To break the jet of water

To bring the runner to rest in a short time

To change the direction of runner

None of these

4

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

Centrifugal pump

Reciprocating pump

Jet pump

Air lift pump

4

# Discharge of a centrifugal pump is (where N = Speed of the pump impeller)

Directly proportional to N

Inversely proportional to N

Directly proportional to N²

Inversely proportional to N²

4

39.2 %

48.8 %

84.8 %

88.4 %