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

C. Diameter of Pelton wheel to the diameter of jet

4

Axial

Centrifugal

Vortex

4

0.25 kW

0.75 kW

1.75 kW

3.75 kW

4

In an inward 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

Turgo turbine

Pelton wheel

Kaplan turbine

4

Puck up the wrong statement about centrifugal pump

Discharge a diameter

Power a speed⁴

4

Medium specific speed of turbine implies it is

Propeller turbine

Francis turbine

Impulse turbine

Any one of the above

4

(D/2d) + 5

(D/2d) + 10

(D/2d) + 15

(D/2d) + 20

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

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

2 to 4

4 to 8

8 to 16

16 to 24

4

102 watts

75 watts

550 watts

735 watts

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

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

Horizontal

Nearly horizontal

Steep

First rise and then fall

4

Remain same

Increases

Decreases

None of these

4

Impulse turbine is generally fitted

At the level of tail race

Little above the tail race

Slightly below the tail race

About 2.5 m above the tail race to avoid cavitations.

4

A ship with jet propulsion draws water through inlet orifices at right angles to the direction of its motion. The propelling force of the jet is (where a = Area of the jet, Vr = Relative velocity of the jet and ship = V + v, v = Velocity of the ship, and V = Velocity of the jet issuing from the ship)

waVr /g × (Vr + v)

waVr /g × (Vr - v)

waVr /g × (Vr + v)²

waVr /g × (Vr - v)²

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

High discharge

4

Multistage centrifugal pumps are used to obtain

High discharge

Pumping of viscous fluids

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 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

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

24.8 r.p.m.

48.2 r.p.m

82.4 r.p.m.

248 r.p.m

4

Maximum impulse will be developed in hydraulic ram when

Waste valve closes suddenly

Supply pipe is long

Supply pipe is short

Ram chamber is large

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

N√P / H3/2

N√P / H²

N√P / H5/4

N√P / H3

4

Indicator diagram of a reciprocating pump is a graph between

Flow vs. swept volume

Pressure in cylinder vs. swept volume

Flow vs. speed

Pressure vs. speed

4

Strain

Pressure

Kinetic

None of these

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