Steam Power Plants MCQs : This section focuses on the "Steam Power Plants" in Electric power system. These Multiple Choice Questions (MCQs) should be practiced to improve the Electric power system skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
The steam-electric power station is a power station in which the electric generator is steam driven.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: True, The steam-electric power station is a power station in which the electric generator is steam driven
Question 2
Most electric power is produced by steam-electric power plants, which produce about _________ of all electric.
A. 0.51
B. 0.63
C. 0.78
D. 0.89
View Answer
Ans : D
Explanation: most electric power is produced by steam-electric power plants, which produce about 89% of all electric
Question 3
The steam vapor picks up energy and is superheated _______ the saturation temperature.
A. below
B. above
C. equal to
D. Can not say
View Answer
Ans : B
Explanation: The steam vapor picks up energy and is superheated above the saturation temperature.
Question 4
Which part of thermal power plant causes maximum energy losses?
A. Alternator
B. Boiler
C. Condenser
D. Ash and unburnt carbon
View Answer
Ans : C
Explanation: About 54% of energy losses occurs in condenser. Losses in boiler and alternator are about 1% and 16% because of such high losses overall efficiency of thermal power plant reduces to 29% for normal old thermal power plant and 50% for modern super critical pressure steam power plant which employs many heat saving devices.
Question 5
What is the effect of increasing steam pressure on efficiency of steam power plant?
A. Increases linearly
B. Increases nonlinearly
C. Decreases linearly
D. Does not changes
View Answer
Ans : B
Explanation: The thermal efficiency of steam power plant depends upon the steam pressure. The efficiency increases with increasing steam pressure nonlinearly up to a level. After that level increase in efficiency becomes very low with respect to increasing pressure.
Question 6
What is the principle of operation of steam power plant?
A. Carnot cycle
B. Brayton cycle
C. Stirling cycle
D. Rankine cycle
View Answer
Ans : D
Explanation: The Rankine cycle is an idealized thermodynamic cycle of heat engine. Under this cycle heat energy is converted into mechanical energy while undergoing phase change. The heat is supplied externally to the closed loop which usually uses water as working fluid.
Question 7
Which of the following material is not used in the boiler furnace walls?
A. Fire clay
B. Silica
C. Concrete
D. Kaolin
View Answer
Ans : C
Explanation: Fire clay, Silica and Kaolin have property of resisting change in shape, weight or physical property at higher temperature. Concrete have no such properties at higher temperature so it is not suitable for that.
Question 8
Which of the following is not a type of steam turbine?
A. Impulse turbine
B. Reaction turbine
C. Pelton wheel turbine
D. Axial flow type turbine
View Answer
Ans : C
Explanation: Pelton wheel turbine is a water turbine. Impulse and reaction turbines are the steam turbines characterized by the action of steam on moving blades. Axial and radial flow turbine and steam turbines are characterized by type of flow of steam over blades
Question 9
Preheating the feedwater reduces the irreversibilities involved in steam generation
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: True, Preheating the feedwater reduces the irreversibilities involved in steam generation.
Question 10
Geothermal plants need ______ boiler
A. 0
B. 1
C. 2
D. 3
View Answer
Ans : A
Explanation: True, Geothermal plants need no boiler since they use naturally occurring steam sources.