Explore topic-wise MCQs in Mechanical Engineering.

This section includes 180 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

101.

Select the incorrect statement which supports PWR.

A. water is used as coolant
B. pwr is stable in operation
C. uses natural fuel
Answer» D.
102.

LWR stands for

A. lower water reactor
B. line water reactor
C. liquefied water reactor
D. light water reactor
Answer» E.
103.

Select the incorrect statement about PWR.

A. high primary circuit pressure requires a strong pressure vessel
B. corrosion is less in pwr
C. during fuel charging in pwr, the reactor has to be shut down at least for a month
D. pwr results in uneven heating
Answer» C. during fuel charging in pwr, the reactor has to be shut down at least for a month
104.

What does the top of the pressurizer in pressurized water reactor consists of at primary system pressure?

A. steam
B. air
C. water
D. fluids
Answer» B. air
105.

PWR stands for

A. power
B. partially weathered rock
C. pressurized water reactor
D. packaging waste regulations
Answer» D. packaging waste regulations
106.

In economics of nuclear power plant taxes and insurance charges are taken as

A. operating cost
B. maintenance cost
C. capital cost
D. fixed cost
Answer» E.
107.

What efficiencies of thermionic power generator have been realised?

A. 50-60%
B. 40-50%
C. 10-20%
D. 30-40%
Answer» D. 30-40%
108.

Which of these is not a component of nuclear reactor?

A. reactor core
B. refractor
C. control rod
D. biological shield
Answer» C. control rod
109.

Which of the following is not a type of Combined Plant?

A. sodium- mercury-potassium plant
B. gas turbine-steam turbine plant
C. thermionic steam plant
D. thermoelectric steam plant
Answer» B. gas turbine-steam turbine plant
110.

What happens to the availability in a combined cycle plant?

A. decreases
B. increases
C. remains same
D. cannot say
Answer» B. increases
111.

The maximum steam temperature in a

A. 600
B. 500
C. 300
D. 100
Answer» B. 500
112.

The gas turbine power plant mainly uses which among the following fuels?

A. coal and peat
B. kerosene oil and diesel oil and residual oil
C. gas oil
D. natural gas and liquid petroleum fuel
Answer» E.
113.

The temperature in a dry bottom pulverised coal furnace, in degree Celsius is about?

A. 1200
B. 1300
C. 1400
D. 2000
Answer» C. 1400
114.

Which type of compressor is used in a gas turbine plant?

A. reciprocating compressor
B. screw compressor
C. multistage axial flow compressor
D. either reciprocating compressor & screw compressor
Answer» D. either reciprocating compressor & screw compressor
115.

What part or % of power developed is utilised for driving the compressor?

A. 65 %
B. 70 %
C. 55 %
D. 80 %
Answer» B. 70 %
116.

A Gas Turbine is which type of combustion plant?

A. external
B. open
C. internal
D. cannot say
Answer» D. cannot say
117.

Power is produced when the working fluid does some work on the?

A. shaft
B. fins
C. blades
D. none of the mentioned
Answer» D. none of the mentioned
118.

What would be the temperature of the gas in the combustion chamber?

A. 500 °c
B. 1600 °c
C. 1200 °c
D. 650 °c
Answer» C. 1200 °c
119.

What is the air standard cycle for a Gas- Turbine called?

A. reheat cycle
B. rankine cycle
C. brayton cycle
D. diesel cycle
Answer» D. diesel cycle
120.

What is meant by inter cooling?

A. removal of heat from compressed air between stages of compression
B. transfer of heat energy from exhaust gases to the compressed air flowing between compressor and the combustion chamber
C. to increase the temperature of partially expanded gases by burning more fuel
D. none of the mentioned
Answer» B. transfer of heat energy from exhaust gases to the compressed air flowing between compressor and the combustion chamber
121.

What is regeneration?

A. removal of heat from compressed air between stages of compression
B. transfer of heat energy from exhaust gases to the compressed air flowing between compressor and the combustion chamber
C. to increase the temperature of partially expanded gases by burning more fuel
D. transfer of heat energy from exhaust gases to the compressed air flowing between compressor and the combustion chamber and increases the temperature of partially expanded gases by burning more fuel
Answer» C. to increase the temperature of partially expanded gases by burning more fuel
122.

Which of these is a working fluid in the bottoming plant of a Brayton-Rankine combined plant?

A. mercury
B. steam
C. water
D. air
Answer» D. air
123.

If e is the electricity fraction of the total energy output, m is the electric plant efficiency and n is the steam generator efficiency; the heat added per unit total energy output is given by?

A. (1 / m) + ((1 – e) / n)
B. (1 / n) + ((1 – e) / m)
C. (1 / m) + ((1 + e) / n)
D. (1 / n) + ((1 – e) / m)
Answer» B. (1 / n) + ((1 – e) / m)
124.

Which of the following is a good medium for constant temperature heating?

A. water
B. steam
C. coolant
D. diesel
Answer» C. coolant
125.

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.
126.

Which of these is not considered economical for cogeneration?

A. a high fraction of electric to total energy
B. a low fraction of electric to total energy
C. a low fraction of total energy to electric energy
D. none of the mentioned
Answer» C. a low fraction of total energy to electric energy
127.

In a by-product power cycle?

A. the power is produced initially
B. power production is in the middle stages of the cycle
C. power production is after the cycle has ended
D. none of the mentioned
Answer» D. none of the mentioned
128.

In terms of cost per MW compared to condensing sets of the same power, the back pressure turbines are?

A. more expensive
B. cheaper
C. costly
D. none of the mentioned
Answer» C. costly
129.

In a back pressure turbine

A. pressure at the exhaust from the turbine is the saturation pressure corresponding to the temperature desired in the process
B. pressure at the entrance of the turbine is the saturation pressure corresponding to the temperature desired in the process
C. pressure at the exhaust from the turbine is the saturation pressure corresponding to the pressure desired in the process
D. none of the mentioned
Answer» B. pressure at the entrance of the turbine is the saturation pressure corresponding to the temperature desired in the process
130.

A plant producing both, electrical power & process heat simultaneously is?

A. cogenital plant
B. cogenerial plant
C. cogeneration plant
D. conglomerate plant
Answer» D. conglomerate plant
131.

Chemical method of treatment is used for treatment of:

A. diissolve gases
B. carbonate and carbon dioxide
C. bacterial impurities
D. send and suspended materials
Answer» C. bacterial impurities
132.

Thermal treatment methods used to remove impurities like:

A. dissolved carbon dioxide and other gases
B. solid materials
C. carbonate
D. bacterial impurities
Answer» B. solid materials
133.

Which method is used in large modern thermal power plants to heat feed water?

A. open type heatre is used
B. close type heater is used
C. steam is directly taken from main turbine and used to heat it feed water
D. surface type heater is used
Answer» D. surface type heater is used
134.

Mechanical method of water treatment is done to

A. heat the feed water
B. to remove solid matter and impurities
C. to add some solid materials
D. to remove dissolved gases
Answer» C. to add some solid materials
135.

Which of these is not a type of drive of variable speed control?

A. variable speed turbine
B. hydraulic coupling
C. multiple speed ac motor
D. electronically adjustable turbine drive
Answer» E.
136.

Feed water for boiler of thermal power plant is obtained from:

A. natural sources like river and lake
B. partly from condensed steam and natural sources
C. condensed steam and small percentage from natural resources
D. natural sources and small percentage from condensed steam
Answer» D. natural sources and small percentage from condensed steam
137.

Which of the following types of the fans has the highest cost?

A. centrifugal fans
B. axial fans
C. primary fans
D. gas recirculation fans
Answer» C. primary fans
138.

In a furnace employing forced draught compared to induced draught

A. the fan operates hot and hence blades are liable to corrosion and erosion
B. positive pressure exists in the furnace
C. air is sucked in, so air leaks are more and hence furnace efficiency is reduced
D. none of the mentioned
Answer» D. none of the mentioned
139.

Which of these accentuates clinkering trouble on furnace grate burning coal?

A. low reactivity of carbonised residue containing high proportions of iron and sulphur
B. low forced draught and low fuel bed temperature
C. thick fire bed and preheated primary air
D. all of the mentioned
Answer» E.
140.

Stack heat losses can be minimised by

A. using low c.v. fuels
B. controlling the excess air
C. oxygen enrichment of combustion air
D. maintaining proper draft in the furnace
Answer» C. oxygen enrichment of combustion air
141.

Which of these is not a type of mechanical draft system for a furnace?

A. balanced draft
B. induced draft
C. forced draft
D. actuated draft
Answer» E.
142.

6 DRAUGHT SYSTEM

A. Δp = gh(ρa-ρg)
B. Δp = gh(ρg-ρa)
C. Δp = ghρg
D. Δp = gh(ρa+ρg)
Answer» B. Δp = gh(ρg-ρa)
143.

What is the capacity of low pressure hydraulic ash handling system?

A. 80 tonnes/hour
B. 22 tonnes/hour
C. 50 tonnes/hour
D. 10 tonnes/hour
Answer» D. 10 tonnes/hour
144.

What would be the amount of distance that a low pressure system could carry the ash?

A. 25m
B. 500m
C. 150m
D. 800m
Answer» C. 150m
145.

Which of these terms defines the pressure difference in the furnace?

A. draught
B. duct
C. stack
D. chimney
Answer» B. duct
146.

Which medium is used to carry ash in hydraulic system?

A. air
B. water
C. steam
D. conveyor
Answer» C. steam
147.

Which system is noisy out of all the following ash handling systems?

A. steam jet ash handling system
B. mechanical ash handling system
C. pneumatic ash handling system
D. hydraulic ash handling system
Answer» D. hydraulic ash handling system
148.

Which medium is used to carry ash in the pneumatic ash handling system?

A. conveyor belt
B. water trough
C. air
D. chain belt
Answer» D. chain belt
149.

What is the function of cyclone separators in pneumatic ash handling system?

A. to separate the lighter dust particles
B. to force up the movement of ash through pipes or tubes
C. to draw out the dust from furnace
D. to separate minute coal particles
Answer» B. to force up the movement of ash through pipes or tubes
150.

The coal is fed to the furnace through

A. conveyor belt
B. wagon tipper
C. hopper
D. crane
Answer» D. crane