Explore topic-wise MCQs in Electrical Engineering.

This section includes 36 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

A 240 H inductor is equivalent to a

A. 0.240 mH inductor
B. 0.000240 mH inductor
C. 240 mH inductor
D. 240 H inductor
Answer» B. 0.000240 mH inductor
2.

The voltage across a coil when = 20 mA/s and = 8 H is

A. 16 mV
B. 160 mV
C. 1.6 mV
D. 2.5 mV
Answer» C. 1.6 mV
3.

An inductance of 0.08 H is larger than

A. 0.0000008 H
B. 0.000000008 H
C. 0.000008 H
D. 0.00008 mH
Answer» C. 0.000008 H
4.

Two inductors, and , are in parallel. has a value of 25 H and a value of 50 H. The parallel combination is in series with , a 20 H coil. The entire combination is across an ac source of 60 V at 300 kHz. The total rms current is

A. 87 mA
B. 870 mA
C. 87 A
D. 337 mA
Answer» C. 87 A
5.

An inductor, a 1 k resistor, and a switch are connected in series across a 6 V battery. At the instant the switch is closed, the inductor voltage is

A. 0 V
B. 6 V
C. 12 V
D. 4 V
Answer» C. 12 V
6.

An 18 V power supply is connected across a coil with a winding resistance of 180 . Current flow in the coil is

A. 1 mA
B. 10 mA
C. 100 mA
D. 1 A
Answer» D. 1 A
7.

A switch, a 220 resistor, and a 60 mH inductor are in series across a 20 V battery. What is the current through the inductor two time constants after the switch is closed?

A. 91 mA
B. 78 mA
C. 57 mA
D. 400 mA
Answer» C. 57 mA
8.

A 320 H coil is in series with a 3.3 k resistor. How long does it take for current to build up to its full value?

A. 0.48 s
B. 0.48 ms
C. 0.48
D. s
E. 48 s
Answer» D. s
9.

Five inductors are connected in series. The lowest value is 8 μH. If the value of each inductor is twice that of the preceding one, and if the inductors are connected in order of ascending values, the total inductance is

A. 8 H
B. 32 μH
C. 64 μH
D. 248 μH
Answer» E.
10.

is directly proportional to frequency and inductance.

A. True
B. False
Answer» B. False
11.

An induced voltage is produced as a result of a dc voltage.

A. True
B. False
Answer» C.
12.

Inductance is the property of an inductor that produces an opposition to any change in current.

A. True
B. False
Answer» B. False
13.

Inductance is indirectly proportional to the square of the number of turns, the permeability, and the cross-sectional area of the core.

A. True
B. False
Answer» C.
14.

Inductors add in parallel.

A. True
B. False
Answer» C.
15.

Energy is stored by an inductor in an electrostatic field.

A. True
B. False
Answer» C.
16.

The term is more commonly used in connection with an inductor used to block off high frequencies.

A. True
B. False
Answer» B. False
17.

All coil cores are made of iron.

A. True
B. False
Answer» C.
18.

Two 10 H inductors are in parallel and the parallel combination is in series with a third 10 H inductor. What is the approximate total reactance when a voltage with a frequency of 7 kHz is applied across the circuit terminals?

A. 219 k
B. 66 k
C. 660 k
D. 1.3 M
Answer» D. 1.3 M
19.

When the current through an inductor is cut in half, the amount of energy stored in the electromagnetic field

A. is quartered
B. quadruples
C. doubles
D. does not change
Answer» B. quadruples
20.

An inductance of 0.43 mH is smaller than

A. 43 H
B. 430 H
C. 0.05 H
D. 0.00043 H
Answer» D. 0.00043 H
21.

The following coils are in parallel: 75 H, 40 H, 25 H, and 15 H. The total inductance is approximately

A. 6.9 H
B. 14 H
C. 2.2 H
D. 155 H
Answer» B. 14 H
22.

An inductor and a resistor are in series with a sine wave voltage source. The frequency is set so that the inductive reactance is equal to the resistance. If the frequency is increased, then

A. VR ‚â• VL
B. VL < VR
C. VL = VR
D. VL > VR
Answer» E.
23.

When the current through an inductor decreases, the amount of energy stored in the electromagnetic field

A. increases
B. decreases
C. remains the same
D. doubles
Answer» C. remains the same
24.

Faraday's law states that relative motion between a magnetic field and a coil induces a voltage across the coil.

A. 1
B.
Answer» B.
25.

Five inductors are connected in series. The lowest value is 8 μH. If the value of each inductor is twice that of the preceding one, and if the inductors are connected in order of ascending values, the total inductance is

A. 8 H
B. 32 μH
C. 64 μH
D. 248 μH
Answer» E.
26.

A switch, a 220 resistor, and a 60 mH inductor are in series across a 20 V battery. What is the current through the inductor two time constants after the switch is closed?

A. 91 mA
B. 78 mA
C. 57 mA
D. 400 mA
Answer» C. 57 mA
27.

The inductance of an iron-core coil decreases if

A. the number of turns is decreased
B. the iron core is removed
C. the length of the coil decreases
D. none of the above
Answer» B. the iron core is removed
28.

Three 15 mH inductors are in series. The total inductance is

A. 15 mH
B. 30 mH
C. 45 mH
D. 5 mH
Answer» D. 5 mH
29.

A 5 mH, a 4.3 mH, and a 0.6 mH inductor are connected in parallel. The total inductance is

A. 9.9 mH
B. greater than 5 mH
C. 9.9 mH or greater than 5 mH
D. less than 0.6 mH
Answer» E.
30.

The winding resistance of a coil can be increased by

A. increasing the number of turns
B. using a thinner wire
C. changing the core material
D. increasing the number of turns or using thinner wire
Answer» E.
31.

The voltage across a coil when di/dt = 20 mA/s and L = 8 H is

A. 16 mV
B. 160 mV
C. 1.6 mV
D. 2.5 mV
Answer» C. 1.6 mV
32.

The permeability of a core material is an indication of the ability of the material to establish a magnetic field.

A. 1
B.
C. 1
D.
Answer» B.
33.

A 2 mH, a 3.3 mH, and a 0.2 mH inductor are connected in series. The total inductance is

A. 55 mH
B. less than 0.2 mH
C. less than 5.5 mH
D. 5.5 mH
Answer» E.
34.

A sine wave voltage is applied across an inductor. When the frequency of the voltage is decreased, the current

A. is increased
B. is decreased
C. does not change
D. momentarily goes to zero
Answer» B. is decreased
35.

A 240 H inductor is equivalent to a

A. 0.240 mH inductor
B. 0.000240 mH inductor
C. 240 mH inductor
D. 240 H inductor
Answer» B. 0.000240 mH inductor
36.

An inductance of 0.08 H is larger than

A. 0.0000008 H
B. 0.000000008 H
C. 0.000008 H
D. 0.00008 mH
Answer» C. 0.000008 H