Explore topic-wise MCQs in Electrical Engineering.

This section includes 187 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

151.

In a regenerative feed heating cycle, the optimum value of the fraction of steam extracted for feed heating?

A. Decreases with increase in Rankine cycle efficiency
B. Increases with increase in Rankine cycle efficiency
C. Is unaffected by increase in Rankine cycle efficiency
D. None of the above
Answer» C. Is unaffected by increase in Rankine cycle efficiency
152.

The effect of considering friction losses in steam nozzle for the same pressure ratio leads to?

A. increase in exit velocity from the nozzle
B. decrease in exit velocity from the nozzle
C. no change in exit velocity from the nozzle
D. increase or decrease depending upon the exit quality of steam
Answer» C. no change in exit velocity from the nozzle
153.

Reheat cycle in steam power plant is used to?

A. utilise heat of flue gases
B. increase thermal efficiency
C. improve condenser performance
D. reduce loss of heat
Answer» C. improve condenser performance
154.

Example of overfeed type stoker is?

A. chain grate
B. spreader
C. travelling grate
D. all of the above
Answer» E.
155.

Rankine cycle operating on low pressure limit of p1 and high pressure limit of p2?

A. Has higher thermal efficiency than the Carnot cycle operating between same pressure limits
B. Has lower thermal efficiency than Carnot cycle operating between same pressure limit
C. Has same thermal efficiency as Carnot cycle operating between same pressure limits
D. May be more or less depending upon the magnitude of p1 and p2
Answer» B. Has lower thermal efficiency than Carnot cycle operating between same pressure limit
156.

In a steam power plant, the function of a condenser is?

A. to maintain pressure below atmospheric to increase work output from the primemover
B. to receive large volumes of steam exhausted from steam prime mover
C. to condense large volumes of steam to water which may be used again in boiler
D. all of the above
Answer» E.
157.

Solar thermal power generation can be achieved by?

A. using focusing collector or heliostates
B. using flat plate collectors
C. using a solar pond
D. any of the above system
Answer» E.
158.

The critical pressure ratio of a convergent nozzle is defined as?

A. the ratio of outlet pressure to inlet pressure of nozzle
B. the ratio of inlet pressure to outlet pressure of nozzle
C. the ratio of outlet pressure to inlet pressure only when mass flow rate per unit area is min-imum
D. the ratio of outlet pressure to inlet pressure only when mass flow rate = c
Answer» E.
159.

Economiser is used to heat?

A. air
B. feed water
C. flue gases
D. all above
Answer» C. flue gases
160.

Load carrying capacity of belt conveyor is about?

A. 20 to 40 tonnes/hr
B. 50 to 100 tonnes/hr
C. 100 to 150 tonnes/hr
D. 150 to 200 tonnes/hr
Answer» C. 100 to 150 tonnes/hr
161.

In steam turbines the reheat factor

A. increases with the increase in number of stages
B. decreases with the increase in number of stages
C. remains same irrespective of number of stages
D. none of the above
Answer» B. decreases with the increase in number of stages
162.

The cooling section in the surface condenser

A. increases the quantity of vapour extracted along with air
B. reduces the quantity of vapour extracted along with air
C. does not affect vapour quantity extracted but reduces pump capacity of air extraction pump
D. none of the above
Answer» C. does not affect vapour quantity extracted but reduces pump capacity of air extraction pump
163.

The average ash content in Indian co als is about

A. 5%
B. 10%
C. 15%
D. 20%
Answer» E.
164.

Rateau steam turbine is

A. reaction steam turbine
B. velocity compounded impulse steam turbine
C. pressure compounded impulse steam turbine
D. pressure velocity compounded steam turbine
Answer» D. pressure velocity compounded steam turbine
165.

A steam power station requires space

A. equal to diesel power station
B. more than diesel power station
C. less than diesel power station
D. none of the above
Answer» C. less than diesel power station
166.

Reheat factor is the ratio of

A. isentropic heat drop to useful heat drop
B. adiabatic heat drop to isentropic heat drop
C. cumulative actual enthalpy drop for the stages to total is isentropic enthalpy heat drop
D. none of the above
Answer» D. none of the above
167.

The draught produced by chimney of given height at given outside temperature

A. decreases if the chimney gas temperature increases
B. increases if the chimney gas temperature increases
C. remains same irrespective of chimney gas temperature
D. may increase or decrease
Answer» C. remains same irrespective of chimney gas temperature
168.

Incase of reaction steam turbine

A. there is enthalpy drop both in fixed and moving blades
B. there is enthalpy drop only in fixed blades
C. there is enthalpy drop only in moving blades
D. none of the above
Answer» B. there is enthalpy drop only in fixed blades
169.

The artificial draught normally is designed to produce

A. less smoke
B. more draught
C. less chimney gas temperature
D. all of the above
Answer» E.
170.

In India largest thermal power station is located at

A. Kota
B. Sarni
C. Chandrapur
D. Neyveli
Answer» D. Neyveli
171.

Method which is commonly applied for unloading the coal for small power plant is

A. lift trucks
B. coal accelerators
C. tower cranes
D. belt conveyor
Answer» C. tower cranes
172.

Blowing down of boiler water is the process

A. to reduce the boiler pressure
B. to increase the steam temperature
C. to control the solid concentration in the boiler water by removing some of the concentrated saline water
D. none of the above
Answer» D. none of the above
173.

The draught produced by steel chimney as compared to that produced by brick chimney for the same height is

A. Less
B. More
C. Same
D. May be more or less
Answer» C. Same
174.

Parson's turbine is

A. pressure compounded steam turbine
B. simple single wheel, impulse steam turbine
C. simple single wheel reaction steam turbine
D. multi wheel reaction steam turbine
Answer» E.
175.

For forced draught system, the function of chimney is mainly

A. to produce draught to accelerate the combustion of fuel
B. to discharge gases high up in the atmosphere to avoid hazard
C. to reduce the temperature of the hot gases discharged
D. none of the above
Answer» C. to reduce the temperature of the hot gases discharged
176.

The percentage O2 by Weight in atmospheric air is

A. 18%
B. 23%
C. 77%
D. 79%
Answer» C. 77%
177.

The value of reheat factor normally varies from

A. 0.5 to 0.6
B. 0.9 to 0.95
C. 1.02 to 1.06
D. 1.2 to 1.6
Answer» D. 1.2 to 1.6
178.

In a surface condenser if air is removed, there is

A. fall in absolute pressure maintained in condenser
B. rise in absolute pressure maintained in condenser
C. no change in absolute pressure in the condenser
D. rise in temperature of condensed steam
Answer» B. rise in absolute pressure maintained in condenser
179.

The ratio of exit pressure to inlet pressure for maximum mass flow rate per unit area of steam through a nozzle when steam is initially dry saturated is

A. 0.6
B. 0.578
C. 0.555
D. 0.5457
Answer» C. 0.555
180.

The thermal efficiency of the engine with condenser as compared to without condenser, for a given pressure and temperature of steam, is

A. Higher
B. Lower
C. Same as long as initial pressure and temperature is unchanged
D. None of the above
Answer» B. Lower
181.

Steam turbines are governed by the following methods

A. Throttle governing
B. Nozzle control governing
C. By-pass governing
D. all of the above
Answer» E.
182.

The energy radiated by sun on a bright sunny day is approximately

A. 700 W/m²
B. 800 W/m²
C. 1 kW/m²
D. 2 kW/m²
Answer» D. 2 kW/m¬¨‚â§
183.

The maximum percentage gain in Regenerative feed heating cycle thermal efficiency

A. increases with number of feed heaters increasing
B. decreases with number of feed heaters increasing
C. remains same unaffected by number of feed heaters
D. none of the above
Answer» B. decreases with number of feed heaters increasing
184.

Belt conveyer can be used to transport coal at inclinations upto

A. 30°
B. 60°
C. 80°
D. 90°
Answer» B. 60¬¨‚àû
185.

The amount of air which is supplied for complete combustion is called

A. primary air
B. secondary air
C. tertiary air
D. none of the above
Answer» C. tertiary air
186.

In De Laval steam turbine

A. the pressure in the turbine rotor is approximately same as in condenser
B. the pressure in the turbine rotor is higher than pressure in the condenser
C. the pressure in the turbine rotor gradually decreases from inlet to exit from condenser
D. none from the above
Answer» B. the pressure in the turbine rotor is higher than pressure in the condenser
187.

Reheat factor in steam turbines depends on

A. exit pressure only
B. stage efficiency only
C. initial pressures and temperature only
D. all of the above
Answer» D. all of the above