Explore topic-wise MCQs in Electrical Engineering Questions.

This section includes 90 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering Questions knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following equipment, for regulating the voltage in distribution feeder, will be most economical?
A. Static condenser
B. Synchronous condenser
C. Tap changing transformer
D. Booster transformer
Answer» E.
Discussion
2.

There is a greater possibility of occurence of corona during______________?
A. dry weather
B. winter
C. summer heat
D. humid weather
E. none of the above
Answer» E. none of the above
Discussion
3.

A 3-phase 4 wire system is commonly used on________________?
A. primary transmission
B. secondary transmission
C. primary distribution
D. secondary distribution
Answer» E.
Discussion
4.

Which of the following is not a constituent for making porcelain insulators ?
A. Quartz
B. Kaolin
C. Felspar
D. Silica
Answer» E.
Discussion
5.

The material commonly used for insulation in high voltage cables is_______________?
A. lead
B. paper
C. rubber
D. none of the above
Answer» C. rubber
Discussion
6.

A booster is a_________________?
A. series wound generator
B. shunt wound generator
C. synchronous generator
D. none of the above
Answer» B. shunt wound generator
Discussion
7.

High voltage transmission lines use__________________?
A. suspension insulators
B. pin insulators
C. both A. and B.
D. none of the above
Answer» B. pin insulators
Discussion
8.

The spacing between phase conductors of a 220 kV line is approximately equal to________________?
A. 2 m
B. 3.5 m
C. 6 m
D. 8.5 m
Answer» D. 8.5 m
Discussion
9.

Which of the following bus-bar schemes has the lowest cost?
A. Ring bus-bar scheme
B. Single bus-bar scheme
C. Breaker and a half scheme
D. Main and transfer scheme
Answer» C. Breaker and a half scheme
Discussion
10.

The loads on distributors systems are generally__________________?
A. balanced
B. unbalanced
C. either of the above
D. none of the above
Answer» C. either of the above
Discussion
11.

Multicore cables generally use________________?
A. square conductors
B. circular conductors
C. rectangular conductors
D. sector-shaped conductors
E. none of the above
Answer» E. none of the above
Discussion
12.

The distributors for residential areas are______________?
A. single phase
B. three-phase three wire
C. three-phase four wire
D. none of the above
Answer» D. none of the above
Discussion
13.

Most of the high transmission lines in Pakistan are_______________?
A. underground
B. overhead
C. either of the above
D. none of the above
Answer» C. either of the above
Discussion
14.

Transmitted power remaining the same, if supply voltage of a D.C. 2-wire feeder is increased 100 percent, saving in copper is____________________?
A. 25 percent
B. 50 percent
C. 75 percent
D. 100 percent
Answer» C. 75 percent
Discussion
15.

The voltage of the single phase supply to residential consumers is_____________?
A. 110 V
B. 210 V
C. 230 V
D. 400 V
Answer» D. 400 V
Discussion
16.

A uniformly-loaded D.C. distributor is fed at both ends with equal voltages. As compared to a similar distributor fed at one end only, the drop at the middle point is______________?
A. one-fourth
B. one-third
C. one-half
D. twice
E. none of the above
Answer» B. one-third
Discussion
17.

Besides a method of trial and error, which of the following methods is employed for solution of network problems in interconnected system ?
A. Circulating current method
B. Thevenin’s theorem
C. Superposition of currents
D. Direct application of Kirehhoffs laws
E. All of the above
Answer» F.
Discussion
18.

Which of the following D.C. distribution system is the simplest and lowest in first cost ?
A. Radial system
B. Ring system
C. Inter-connected system
D. None of the above
Answer» B. Ring system
Discussion
19.

The minimum clearance between the ground and a 220 kV line is about_________________?
A. 4.3 m
B. 5.5 m
C. 7.0 m
D. 10.5 m
Answer» D. 10.5 m
Discussion
20.

Large industrial consumers are supplied electrical energy at__________________?
A. 400 V
B. 11 kV
C. 66 kV
D. 400 kV
Answer» C. 66 kV
Discussion
21.

A feeder, in a transmission system, feeds power to________________?
A. distributors
B. generating stations
C. service mains
D. all of the above
Answer» B. generating stations
Discussion
22.

The material generally used for armour of high voltage cables is_____________?
A. aluminium
B. steel
C. brass
D. copper
Answer» C. brass
Discussion
23.

Which of the following materials is used for overhead transmission lines ?
A. Steel cored aluminium
B. Galvanised steel
C. Cadmium copper
D. Any of the above
Answer» E.
Discussion
24.

In transmission lines the cross-arms are made of________________?
A. copper
B. wood
C. R.C.C.
D. steel
Answer» E.
Discussion
25.

The material commonly used for sheaths of underground cables is______________?
A. lead
B. rubber
C. copper
D. iron
Answer» B. rubber
Discussion
26.

Overhead lines generally use__________________?
A. copper conductors
B. all aluminium conductors
C. A.C.S.R. conductors
D. none of these
Answer» D. none of these
Discussion
27.

The power factor of industrial loads is generally______________?
A. unity
B. lagging
C. leading
D. zero
Answer» C. leading
Discussion
28.

The power transmitted will be maximum when____________?
A. corona losses are minimum
B. reactance is high
C. sending end voltage is more
D. receiving end voltage is more
Answer» B. reactance is high
Discussion
29.

As compared to a 2-wire D.C. distributor, a 3-wire distributor with same maximum voltage to earth uses only__________________?
A. 31.25 percent of copper
B. 33.3 percent of copper
C. 66.7 percent of copper
D. 125 percent of copper
Answer» B. 33.3 percent of copper
Discussion
30.

For an overhead line, the surge impedance is taken as________________?
A. 20-30 ohms
B. 70—80 ohms
C. 100—200 ohms
D. 500—1000 ohms
E. none of the above
Answer» D. 500—1000 ohms
Discussion
31.

The presence of ozone due to corona is harmful because it________________?
A. reduces power factor
B. corrodes the material
C. gives odour
D. transfer energy to the ground
E. none of the above
Answer» C. gives odour
Discussion
32.

A circuit is disconnected by isolators when____________?
A. line is energized
B. there is no current in the line
C. line is on full load
D. circuit breaker is not open
Answer» C. line is on full load
Discussion
33.

Which of the following is usually not the generating voltage ?
A. 6.6 kV
B. 8.8 kV
C. 11 kV
D. 13.2 kV
Answer» C. 11 kV
Discussion
34.

By which of the following methods string efficiency can be improved?
A. Using a guard ring
B. Grading the insulator
C. Using long cross arm
D. Any of the above
E. None of the above
Answer» E. None of the above
Discussion
35.

Pin type insulators are generally not used for voltages beyond_________?
A. 1 kV
B. 11 kV
C. 22 kV
D. 33 kV
Answer» E.
Discussion
36.

In AC.S.R. conductors, the insulation between aluminium and steel conductors is_________?
A. insulin
B. bitumen
C. varnish
D. no insulation is required
Answer» E.
Discussion
37.

Owing to skin effect:
A. current flows through the half cross-section of the conductor
B. portion of the conductor near the surface carries more current and core of the conductor carries less current
C. portion of the conductor near the surface carries less current and core of the conductor carries more cur¬rent
D. any of the above
E. none of the above
Answer» C. portion of the conductor near the surface carries less current and core of the conductor carries more cur¬rent
Discussion
38.

Which of the following materials is not used for transmission and distribution of electrical power________________?
A. Copper
B. Aluminium
C. Steel
D. Tungsten
Answer» E.
Discussion
39.

The current drawn by the line due to corona losses is___________?
A. non-sinusoidal
B. sinusoidal
C. triangular
D. square
Answer» B. sinusoidal
Discussion
40.

The use of strain type insulators is made where the conductors are__________?
A. dead ended
B. at intermediate anchor towers
C. any of the above
D. none of the above
Answer» D. none of the above
Discussion
41.

The voltage drop, for constant voltage transmission is compensated by installing__________?
A. inductors
B. capacitors
C. synchronous motors
D. all of above
E. none of the above
Answer» D. all of above
Discussion
42.

Galvanised steel wire is generally used as______________?
A. stay wire
B. earth wire
C. structural components
D. all of the above
Answer» E.
Discussion
43.

jCorona usually occurs when the electrostatic stress in air around the conductor exceeds?
A. 6.6 kV (r.m.s. value)/cm
B. 11 kV (r.m.s. value)/cm
C. 22 kV (maximum value)/cm
D. 30 kV (maximum value)/cm
Answer» E.
Discussion
44.

For which of the following equipment current rating is not necessary?
A. Circuit breakers
B. Isolators
C. Load break switch
D. Circuit breakers and load break switches
Answer» C. Load break switch
Discussion
45.

In a substation the following equipment is not installed?
A. exciters
B. series capacitors
C. shunt reactors
D. voltatre transformers
Answer» B. series capacitors
Discussion
46.

If variable part of annual cost on account of interest and depreciation on the capital outlay is equal to the annual cost of electrical energy wasted in the conductors, the total annual cost will be minimum and the corresponding size of conductor will be most economical. This statement is known as___________________?
A. Kelvin’s law
B. Ohm’s law
C. Kirchhoffs law
D. Faraday’s law
E. none of the above
Answer» B. Ohm’s law
Discussion
47.

Overhead system can be designed for operation up to____________?
A. 11 kV
B. 33 kV
C. 66 kV
D. 400 kV
Answer» E.
Discussion
48.

The usual spans with R.C.C. poles are_______________?
A. 40—50 meters
B. 60—100 meters
C. 80—100 meters
D. 300—500 meters
Answer» D. 300—500 meters
Discussion
49.

The wooden poles well impregnated with creosite oil or any preservative compound have life_____________?
A. from 2 to 5 years
B. 10 to 15 years
C. 25 to 30 years
D. 60 to 70 years
Answer» D. 60 to 70 years
Discussion
50.

For transmission of power over a distance of 500 km, the transmission voltage should be in the range?
A. 150 to 220 kV
B. 100 to 120 kV
C. 60 to 100 kV
D. 20 to 50 kV
Answer» B. 100 to 120 kV
Discussion