Which of the following pump is successfully used for lifting water to the turbines?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump
Correct Answer :
C. Jet pump
Related Questions
The impeller of a centrifugal pump may have
Volute casing
Volute casing with guide blades
Vortex casing
Any one of these
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
Manometric head, in case of a centrifugal pump, is equal to
Suction lift + Loss of head in suction pipe due to friction + Delivery lift + Loss of head in delivery pipe due to friction + Velocity head in the delivery pipe
Workdone per kN of water Losses within the impeller
Energy per kN at outlet of impeller Energy per kN at inlet of impeller
All of the above
One horsepower is equal to
102 watts
75 watts
550 watts
735 watts
High specific speed of a pump implies it is
Centrifugal pump
Mixed flow pump
Axial flow pump
Any one of the above
Air vessels in reciprocating pump are used to
Smoothen flow
Reduce acceleration to minimum
Increase pump efficiency
Save pump from cavitations
For small discharge at high pressure, following pump is preferred
Centrifugal
Axial flow
Mixed flow
Reciprocating
Centrifugal pump is started with its delivery valve
Kept fully closed
Kept fully open
Irrespective of any position
Kept 50% open
The efficiency of a hydraulic press is given by (where W = Weight lifted by ram, P = Force applied on plunger, A = Area of ram, and a = Area of plunger)
(W/p) × (A/a)
(p/W) × (a/A)
(W/p) × (a/A)
(p/W) × (A/a)
The speed ratio in case of Francis turbine varies from
0.15 to 0.3
0.4 to 0.5
0.6 to 0.9
1 to 1.5
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
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
In a Kaplan turbine runner, the numbers of blades are generally between
2 to 4
4 to 8
8 to 16
16 to 24
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
In impulse Turbine, energy available at the inlet is in the form of
Potential Energy
Strain Energy
Kinetic energy
None of these
Mechanical 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
A Pelton wheel develops 1750 kW under a head of 100 metres while running at 200 r.p.m. and discharging 2500 litres of water per second. The unit speed of the wheel is
10 r.p.m.
20 r.p.m.
40 r.p.m.
80 r.p.m.
Which of the following pump is successfully used for lifting water to the turbines?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump
In order to avoid cavitation in centrifugal pumps
The suction pressure should be high
The delivery pressure should be high
The suction pressure should be low
The delivery pressure should be low
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
The specific speed of a centrifugal pump, delivering 750 litres of water per second against a head of 15 metres at 725 r.p.m., is
24.8 r.p.m.
48.2 r.p.m
82.4 r.p.m.
248 r.p.m
In a Francis turbine runner, the numbers of blades are generally between
2 to 4
4 to 8
8 to 16
16 to 24
The force exerted by a jet of water impinging normally on a plate which due to the impact of jet, moves in the direction of jet with a velocity v is
[wa (V - v)]/2g
[wa (V - v)]/g
[wa (V - v)²]/2g
[wa (V - v²)]/g
Which of the following is not an impulse turbine?
Girad turbine
Turgo turbine
Pelton wheel
Kaplan turbine
Which of the following pump is successfully used for lifting water from deep wells?
Centrifugal pump
Reciprocating pump
Jet pump
Air lift pump
The gross or total head of the turbine is the ________ of the water levels at the head race and tail race.
Sum
Difference
Product
None of these
The working of which of the following hydraulic units is based on Pascal's law?
Air lift pump
Jet pump
Hydraulic coupling
Hydraulic press
The relation between hydraulic efficiency (ηh), mechanical efficiency (ηm) and overall efficiency (ηo) is
ηh = ηo × ηm
ηm = ηm × ηh
ηo = ηh × ηm
None of these
Which of the following is not a reaction turbine?
Fourneyron turbine
Journal turbine
Thomson's turbine
Pelton wheel
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