81 practice sets · Page 1 of 5
Which of the following turbine is preferred for 0 tom head of water?
None of the mentioned
Francis Turbine
Pelton Turbine
Kaplan Turbine
Correct Answer: D — Kaplan Turbine
Explanation:
Kaplan turbine is preferred for low heads of water.
Discharge of a centrifugal pump is __________
directly proportional to (diameter)2 of its impeller
inversely proportional to diameter of its impeller
inversely proportional to (diameter)2 of its impeller
directly proportional to diameter of its impeller
Correct Answer: C — inversely proportional to (diameter)2 of its impeller
Explanation:
Discharge of a centrifugal pump is inversely proportional to (diameter)2 of its impeller.
A hydraulic coupling belongs to the category of __________
power absorbing machines
energy transfer machines
power developing machines
energy generating machines
Correct Answer: B — energy transfer machines
Explanation:
A hydraulic coupling belongs to the category of energy transfer machines.
Multi-stage centrifugal pumps are used to __________
pump viscous fluids
give high discharge
all of the mentioned
produce high heads
Correct Answer: D — produce high heads
Explanation:
Multi-stage centrifugal pumps are used to produce high heads.
Slip of a reciprocating pump is defined as the __________
difference of theoretical discharge and the actual discharge
product of theoretical discharge and the actual discharge
ratio of actual discharge to the theoretical discharge
sum of actual discharge and the theoretical discharge
Correct Answer: A — difference of theoretical discharge and the actual discharge
Explanation:
Slip of a reciprocating pump is defined as the difference of theoretical discharge and the actual discharge.
A centrifugal pump will start delivering liquid only when the pressure rise in the impeller is equal to the __________
static head
velocity head
manometric head
kinetic head
Correct Answer: C — manometric head
Explanation:
A centrifugal pump will start delivering liquid only when the pressure rise in the impeller is equal to the manometric head.
Geometric similarity is said to exist between the model and the prototype if both of them __________
are identical in shape, but differ only in size
have identical velocities
are equal in size and shape
have identical forces
Correct Answer: A — are identical in shape, but differ only in size
Explanation:
Geometric similarity is said to exist between the model and the prototype, if both of them are identical in shape, but differ only in size.
The speed of an imaginary turbine, identical with the given turbine, which will develop a unit power under a unit head, is known as?
unit speed
terrific speed
specific velocity
specific speed
Correct Answer: D — specific speed
Explanation:
The speed of an imaginary turbine, identical with the given turbine, which will develop a unit power under a unit head, is known as Specific Speed.
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
Energy per kN at outlet of impeller – Energy per kN at inlet of impeller
All of the mentioned
Workdone per kN of water – Losses within the impeller
Correct Answer: C — All of the mentioned
Explanation:
Manometric head, in case of a centrifugal pump = 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 = Energy per kN at outlet of impeller – Energy per kN at inlet of impeller = Workdone per kN of water – Losses within the impeller.
The overall efficiency of a reaction turbine is the ratio of __________
workdone on the wheel to the energy (or head of water) actually supplied to the turbine
none of the mentioned
actual work available at the turbine to the energy imparted to the wheel
power produced by the turbine to the energy actually supplied by the turbine
Correct Answer: D — power produced by the turbine to the energy actually supplied by the turbine
Explanation:
The overall efficiency of a reaction turbine is the ratio of power produced by the turbine to the energy actually supplied by the turbine.
A Francis turbine is used when the available head of water is?
25 to 250 m
250 m
none of the mentioned
0 to 25 m
Correct Answer: A — 25 to 250 m
Explanation:
Francis Turbine is used for high heads of water.
The maximum number of jets, generally, employed in an impulse turbine without jet interference are __________
5
6
2
7
Correct Answer: C — 2
Explanation:
The maximum number of jets, generally, employed in an impulse turbine without jet interference are 2.
What is the mechanical efficiency of an impulse turbine?
ratio of the actual work available at the turbine to the energy imparted to the wheel
ratio of the actual power produced by the turbine to the energy actually supplied by the turbine
none of the mentioned
ratio of the Work done on the wheel to the energy of the jet
Correct Answer: A — ratio of the actual work available at the turbine to the energy imparted to the wheel
Explanation:
The mechanical efficiency of an impulse turbine is ratio of the actual work available at the turbine to the energy imparted to the wheel.
Fuel cells are ___________
Nuclear cell
Chromium cell
Carbon cell
Hydrogen battery
Correct Answer: D — Hydrogen battery
Explanation:
Hydrogen battery cells are called fuel cells.
A fuel cell, in order to produce electricity, burns ___________
Helium
None of the mentioned
Nitrogen
Hydrogen
Correct Answer: D — Hydrogen
Explanation:
A fuel cell, in order to produce electricity, burns Hydrogen.
Steam reforming is currently the least expensive method of producing ___________
Natural gas
Hydrogen
Biogas
Coal
Correct Answer: B — Hydrogen
Explanation:
Steam reforming is currently the least expensive method of producing Hydrogen.
Which among the following is not an adverse environmental impact of tidal power generation?
None of the mentioned
Navigational hazard
Interference with spewing and migration of fish
Pollution and health hazard in the estuary due to blockage of flow of polluted water into the sea
Correct Answer: A — None of the mentioned
Explanation:
None of the mentioned impacts are adverse impacts of tidal power generation.
Horizontal axis and vertical axis are the types of ___________
Wind mills
Biogas reactor
Nuclear reactor
Solar cell
Correct Answer: A — Wind mills
Explanation:
Horizontal axis and vertical axis are the types of wind mills.
Photovoltaic energy is the conversion of sunlight into ___________
Geothermal energy
Biogas
Chemical energy
Electricity
Correct Answer: C — Chemical energy
Explanation:
Photovoltaic energy is the conversion of sunlight into Chemical Energy.
Which of the following is a disadvantage of most of the renewable energy sources?
Highly polluting
Unreliable supply
High waste disposal cost
High running cost
Correct Answer: B — Unreliable supply
Explanation:
Unreliable supply is a disadvantage of most of the renewable energy sources.
