Explore topic-wise MCQs in Power Plant.

This section includes 102 Mcqs, each offering curated multiple-choice questions to sharpen your Power Plant knowledge and support exam preparation. Choose a topic below to get started.

51.

Efficiency of a Rankine Cycle is also expressed as__________

A. Capacity Ratio
B. Heat Rate
C. Heat Ratio
D. Steam Rate
Answer» C. Heat Ratio
52.

Name the major isotope present in steam generated in a Boiling Water Reactor.

A. N-16
B. D-32
C. N-32
D. D-16
Answer» B. D-32
53.

What percentage of fuel energy is actually converted to electrical energy?

A. 0.5
B. 0.4
C. 0.34
D. 0.25
Answer» D. 0.25
54.

Which of these is a 'fissile fuel'?

A. Thorium
B. Carbon
C. Potassium
D. Graphite
Answer» B. Carbon
55.

The temperature to which air must be cooled in order to become saturated is the

A. minimum temperature
B. dew point temperature
C. wet-bulb temperature
D. freezing point
Answer» C. wet-bulb temperature
56.

Critical pressure of water is

A. 1 kg / cm2
B. 100 kg / cm2
C. 155 kg / cm2
D. 217.7 kg / cm2
Answer» E.
57.

Which of these shouldn't be there in the pipelines of working fluid for achieving the conditions of Carnot Cycle?

A. Heat Transfer
B. Insulation
C. Lubrication
D. Zero Friction
Answer» B. Insulation
58.

What is the value of “beta” if h represents the local enthalpy on the given expansion line at a given pressure & hf is the enthalpy of saturated water at that pressure?

A. h + hf
B. h x hf
C. h – hf
D. none of the mentioned
Answer» D. none of the mentioned
59.

Where is the deaerator placed in the feedwater system?

A. in the beginning
B. in the middle
C. at the end
D. there is no deaerator in the feedwater system
Answer» C. at the end
60.

Which gases are vented out of the deaerator?

A. Oxygen only
B. Carbon dioxide only
C. Oxygen & Carbon dioxide both
D. None of the mentioned
Answer» D. None of the mentioned
61.

Coal used in power plant is also known as

A. steam coal
B. charcoal
C. coke
D. soft coal
Answer» B. charcoal
62.

What approximate percentage of energy in the fuel is converted to electricity?

A. 0.55
B. 0.45
C. 0.35
D. 0.25
Answer» D. 0.25
63.

Which of the following is not a component of Brayton cycle?

A. Compressor
B. Combustion Chamber
C. Turbine
D. Pump
Answer» E.
64.

Which of these is a disadvantage of open heater?

A. simplicity
B. lower cost
C. high heat transfer capacity
D. none of the mentioned
Answer» E.
65.

Which of these is an output of a 'Furnace'?

A. Fuel gas
B. Air
C. Flue gases
D. Water Vapor
Answer» D. Water Vapor
66.

Which of these is a 'working fluid' in liquid phase?

A. Water
B. Steam
C. Mercury
D. Oxygen
Answer» B. Steam
67.

Why is the deaerator placement in the feedwater system so important?

A. to maximise pressure difference between the condenser & the boiler
B. to minimise pressure difference between the condenser & the boiler
C. to make the pressure difference between the condenser & the boiler Zero
D. none of the mentioned
Answer» D. none of the mentioned
68.

In the T-S diagram of a Rankine cycle, the abscissa represents?

A. total entropy of turbine steam
B. partial entropy of turbine steam
C. partial enthalpy of turbine steam
D. none of the mentioned
Answer» B. partial entropy of turbine steam
69.

Which of these constitute a Carnot Cycle?

A. 2 reversible isotherms & 2 reversible adiabatics
B. 1 reversible isotherms & 2 reversible adiabatics
C. 2 reversible isotherms & 1 reversible adiabatics
D. 1 reversible isotherms & 2 reversible adiabatics
Answer» B. 1 reversible isotherms & 2 reversible adiabatics
70.

Is regenerative cycle alone useful?

A. Yes
B. No
C. may be
D. depends on other factors
Answer» B. No
71.

What is the most preferable dryness fraction of the exhaust steam?

A. 0.99
B. 0.77
C. 0.66
D. 0.88
Answer» E.
72.

If q represents the work output, r represents the work input, Q represents the heat input, the efficiency n in terms of q & r is given by?

A. n = (q-r)/Q
B. n = ( q+r)/Q
C. n = (qr)/Q
D. n = (qr x qr)/Q
Answer» B. n = ( q+r)/Q
73.

Apart from alloying, name a material that is used instead of ferritic steels to increase the ultimate strength of unalloyed steels.

A. Chromium
B. Molybdenum
C. " Austenitic steelb) None of the mentionedView AnswerAnswer: cExplanation: The use of Austenitic steels increases the ultimate strength of unalloyed steels at high temperatures. The temperature limits are in the range 538-565 degree Centigrade.9. Which of these cases will have a higher cycle efficiency?a) Condenser Pressure= 25 mm of Hg; C
D. Condenser Pressure= 100 mm of Hg; Cooling Water Temperature= 45 degree Centigrade
Answer» B. Molybdenum
74.

The mechanical efficiency of a turbine is given by? (ntm denotes the mechanical efficiency)

A. ntm = (brake output of the turbine x internal output of the turbine)
B. ntm = (internal output of the turbine / break output of the turbine)
C. ntm = (brake output of the turbine / internal output of the turbine)
D. ntm = (brake output of the turbine – internal output of the turbine)
Answer» D. ntm = (brake output of the turbine – internal output of the turbine)
75.

Which of the following is not an advantage of an open heater?

A. simplicity
B. lower cost
C. high heat transfer capacity
D. necessity of a pump at each heater to handle the large feedwater stream
Answer» E.
76.

Function of surge tank?

A. Regulation of water pressure
B. Regulation of steam pressure
C. Storage
D. Regulation of lubricants
Answer» B. Regulation of steam pressure
77.

Efficiency of a power plant is more in summers or winters?

A. summers
B. winters
C. same in both
D. depends on variation
Answer» C. same in both
78.

Which of the following shows the correct relation? (nboiler denotes efficiency of a boiler)

A. nboiler = (rate of energy absorption by water to form steam / rate of energy released by the combustion of fuel)
B. nboiler = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel)
C. nboiler = (rate of energy absorption by water to form steam – rate of energy released by the combustion of fuel)
D. nboiler = (rate of energy absorption by water to form steam x rate of energy released by the combustion of fuel)
Answer» B. nboiler = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel)
79.

What is the effect of increase in steam rate on boiler size?

A. boiler size increases
B. boiler size increases
C. boiler size is independent of steam rate
D. none of the mentioned
Answer» B. boiler size increases
80.

A Hydraulic Ram Pump is based on the principle of?

A. Wind Hammer
B. Water hammer
C. Wind gushing
D. None of the mentioned
Answer» C. Wind gushing
81.

“Regenerative feedwater heating by turbine extraction” is often termed as?

A. Electrophoresis of Rankine cycle
B. Sterlinisation of Rankine cycle
C. Carnotization of Rankine cycle
D. None of the mentioned
Answer» D. None of the mentioned
82.

If Q1 represents the rate of heat addition to the cycle and W represents net cycle work output, the expression for net cycle heat rate is ?

A. Q1 + W
B. Q1 / W
C. Q1 / (1/ W)
D. Q1 x W
Answer» C. Q1 / (1/ W)
83.

What is the exhaust condition of a Watt's Beam Engine?

A. near saturation
B. dry
C. wet
D. 0.9 dry
Answer» D. 0.9 dry
84.

The area of parallelogram in the T-S diagram representing the cycle output is equal to?

A. area of rectangle representing the output of the Carnot cycle
B. area of the triangle representing the output of the Carnot cycle
C. area of the square representing the output of the Carnot cycle
D. none of the mentioned
Answer» B. area of the triangle representing the output of the Carnot cycle
85.

If plant efficiency is high, what will be its effect on heater size?

A. it remains same
B. it increases
C. it decreases
D. none of the mentioned
Answer» C. it decreases
86.

Reheat is preferred for the plants having efficiency greater than

A. 150MW
B. 200MW
C. 100MW
D. 250MW
Answer» D. 250MW
87.

In an ideal regenerative cycle, the work output is at?

A. Boiler
B. Turbine
C. Condenser
D. Pump
Answer» C. Condenser
88.

Heat rejection in a condenser is to?

A. cooled water
B. coolant
C. cooling water
D. none of the mentioned
Answer» D. none of the mentioned
89.

The expression for the overall temperature difference T is given by?

A. t = boiler saturation temperature – condenser temperature
B. t = boiler saturation temperature + condenser temperature
C. t = boiler saturation temperature x condenser temperature
D. t = boiler saturation temperature / condenser temperature
Answer» B. t = boiler saturation temperature + condenser temperature
90.

The cogeneration plant efficiency nco if WT, Qi, QH represents turbine work, heat input, heat output respectively is given by?

A. nCO = (WT + Qi) / QH
B. nCO = (WT – Qi) / QH
C. nCO = (WT + QH) / Qi
D. nCO = (WT + QH) / Qi
Answer» E.
91.

Among 1 MW, 2 MW, 30 MW & 660 MW locomotive steam engines, the highest initial temperature is of?

A. 1 MW
B. 2 MW
C. 30 MW
D. 660 MW
Answer» E.
92.

Steam used to heat water comes from?

A. boiler
B. turbine
C. condenser
D. external power source
Answer» C. condenser
93.

THE_COMPONENTS_OF_A_STEAM_POWER_PLANT_ARE??$

A. Evaporator, Condenser, Boiler, Expansion valve
B. Evaporator, Condenser, Boiler, Turbine
C. Boiler, Turbine, Condenser, Pump
D. Boiler, Turbine, Pump, Expansion valve
Answer» D. Boiler, Turbine, Pump, Expansion valve
94.

Shaft_work_is_fed_to____________for_getting_an_electrical_output.$

A. Motor
B. Generator
C. Rotor
D. Accelerator
Answer» C. Rotor
95.

The product of efficiency & heat transferred to the working fluid is?

A. Net temperature change
B. Net work done
C. Net enthalpy change
D. None of the mentioned
Answer» C. Net enthalpy change
96.

The net change in internal energy in a steam power plant is?

A. Positive
B. Negative
C. Zero
D. None of the mentioned
Answer» D. None of the mentioned
97.

Water that is fed back to the boiler by the pump is called?

A. Adsorbate
B. Absorbate
C. Condenset
D. Condensate
Answer» E.
98.

What kind of a process does a ‘Steam Power Plant’ undergoes?$

A. Adiabatic
B. Cyclic
C. Irreversible
D. Expansion
Answer» C. Irreversible
99.

What kind of energy output is obtained from a ‘Steam Power Plant’?$

A. Heat energy
B. Sound energy
C. Electricity
D. Thermal energy
Answer» D. Thermal energy
100.

Which of these is an output of a ‘Furnace’?$

A. Fuel gas
B. Air
C. Flue gases
D. Water Vapor
Answer» D. Water Vapor