45 + Mcqs in Inductance in a DC Circuit in Electrical Engineering Page 1 McqOptions

1.	Find the time taken for the current in an inductor to change to 2A from 0A if the power in the inductor is 5W. The value of inductance is 10H.
A.	1s
B.	2s
C.	3s
D.	4s
Answer» E.

Discussion

2.	If the current in one coil becomes steady, the current in neighbouring coil is?
A.	Zero
B.	Infinity
C.	Doubles
D.	Halves
Answer» B. Infinity

Discussion

3.	Calculate the value of emf in an inductor if the value of inductance is 15H and an average current of 5A flows through it in 10s.
A.	15V
B.	7.5V
C.	10V
D.	5.5V
Answer» C. 10V

Discussion

4.	Calculate the current in an inductor if the energy stored is 160J and the inductance is 20H.
A.	1A
B.	2A
C.	3A
D.	4A
Answer» E.

Discussion

5.	Practical application of mutual inductance is ____________
A.	DC generator
B.	AC generator
C.	Transformer
D.	Capacitor
Answer» D. Capacitor

Discussion

6.	The flux linkage in coil 1 is 3Wb and it has x turns and the current in coil 2 is 2A, calculate the value of x if the mutual inductance is 750H.
A.	300
B.	400
C.	500
D.	700
Answer» D. 700

Discussion

7.	If the flux linkage in coil 1 is 3Wb and it has 500 turns and the current in coil 2 is 2A, calculate the mutual inductance.
A.	750H
B.	500H
C.	450H
D.	900H
Answer» B. 500H

Discussion

8.	The flux linkage in coil 1 is x and it has 500 turns and the current in coil 2 is 2A, calculate the value of x if the mutual inductance is 750H.
A.	1Wb
B.	2Wb
C.	3Wb
D.	4Wb
Answer» D. 4Wb

Discussion

9.	The flux linkage in coil 1 is 3 Wb and it has 500 turns and the current in coil 2 is xA, calculate the value of x if the mutual inductance is 750H.
A.	1A
B.	2A
C.	3A
D.	4A
Answer» C. 3A

Discussion

10.	The types of inductors are ____________
A.	Fixed and variable
B.	Only fixed
C.	Only variable
D.	Neither fixed nor variable
Answer» B. Only fixed

Discussion

11.	A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the initial value of the current in the circuit.
A.	5A
B.	10A
C.	0 A
D.	20A
Answer» D. 20A

Discussion

12.	A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the value of voltage 1s after the switch is closed.
A.	5.4V
B.	10.8V
C.	0 V
D.	2.7V
Answer» E.

Discussion

13.	The charging time constant of a circuit consisting of an inductor is the time taken for the current in the inductor to become __________% of the initial current.
A.	33
B.	63
C.	37
D.	36
Answer» C. 37

Discussion

14.	A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the initial value of the voltage across the inductor.
A.	5V
B.	10V
C.	0 V
D.	20V
Answer» E.

Discussion

15.	What is the energy stored in the magnetic field if the current in a coil has a constant inductance of L henrys grows at a uniform rate?
A.	LI/2
B.	LI2/2
C.	L/2I
D.	L/2I2
Answer» C. L/2I

Discussion

16.	A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the final value of the voltage across the inductor.
A.	5V
B.	10V
C.	0 V
D.	20V
Answer» D. 20V

Discussion

17.	Initially, when the switch in a series RL circuit is closed, the current in the inductor is?
A.	Maximum
B.	Minimum
C.	Zero
D.	Infinity
Answer» D. Infinity

Discussion

18.	Calculate the number of turns in an inductor with a ferromagnetic core when the inductance is 4000 H, the current changes from 5A to 7A and the flux changes from 760 to 800 Wb.
A.	100
B.	200
C.	300
D.	400
Answer» C. 300

Discussion

19.	Calculate the change in current in an inductor having inductance 4000H, number of turns is 200 and the flux changes from 760 to 800 Wb.
A.	2A
B.	4A
C.	6A
D.	8A
Answer» B. 4A

Discussion

20.	When a ferromagnetic core is inserted into an inductor, what happens to the flux linkage?
A.	Increases
B.	Decreases
C.	Remains the same
D.	Becomes zero
Answer» B. Decreases

Discussion

21.	If tan ? = 10 and the resistance is 2 ohm, calculate the inductive reactance.
A.	10 ohm
B.	20 ohm
C.	30 ohm
D.	40 ohm
Answer» C. 30 ohm

Discussion

22.	A laminated steel ring is wound with 200 turns. When the magnetizing current varies between 5 and 7 A, the magnetic flux varies between 760 and 800 Wb. Calculate the inductance of the coil.
A.	40H
B.	4 H
C.	4000H
D.	0.004 H
Answer» D. 0.004 H

Discussion

23.	Among the following, which is the right formula for inductance of N turns?
A.	L=et/Ni
B.	L=Ni e*t
C.	L=Ni/et
D.	L=N/iet
Answer» B. L=Ni e*t

Discussion

24.	For a coil having a magnetic circuit of constant reluctance, the flux is ___________ to the current.
A.	Directly proportional
B.	Inversely proportional
C.	Not related
D.	Very large compared to
Answer» B. Inversely proportional

Discussion

25.	An induced emf is said to be ________
A.	Inductive
B.	Capacitive
C.	Resistive
D.	Cannot be determined
Answer» B. Capacitive

Discussion

26.	What is the unit for inductive reactance?
A.	Henry
B.	Ohm
C.	Farad
D.	Volts
Answer» C. Farad

Discussion

27.	If the resistance in a circuit is 2 ohm and the impedance is 20 ohm, calculate the power factor.
A.	1/10
B.	1/20
C.	1/30
D.	1/40
Answer» B. 1/20

Discussion

28.	If the power factor is 1/10 and the value of impedance is 20 ohm, calculate the resistance in the circuit.
A.	1 ohm
B.	2 ohm
C.	3 ohm
D.	4 ohm
Answer» C. 3 ohm

Discussion

29.	Among the following, which is the right formula for inductance?
A.	L=emf*t/I
B.	L=emf/t*I
C.	L=emf*I/t
D.	L=emftI
Answer» B. L=emf/t*I

Discussion

30.	Calculate the resistance in an inductive circuit whose time constant is 2s and the inductance is 10H.
A.	7ohm
B.	10ohm
C.	2ohm
D.	5ohm
Answer» E.

Discussion

31.	Calculate the change in flux of an inductor having inductance 4000 H, number of turns is 200 and the current changes from 5A to 7A.
A.	20 Wb
B.	40 Wb
C.	60 Wb
D.	80 Wb
Answer» C. 60 Wb

Discussion

32.	The charging time constant of a circuit consisting of an inductor is the time taken for the voltage in the inductor to become __________ % of the initial voltage.
A.	33
B.	63
C.	37
D.	36
Answer» D. 36

Discussion

33.	Calculate the initial current in an inductor having inductance 4000 H, number of turns is 200 and the flux changes from 760 to 800 Wb. Current changes to 7A.
A.	10A
B.	2A
C.	3A
D.	5A
Answer» E.

Discussion

34.	Calculate the final flux in an inductor having inductance 4000 H, number of turns is 200 and the current changes from 5A to 7A. The initial flux is 760 Wb.
A.	200 Wb
B.	400 Wb
C.	600 Wb
D.	800 Wb
Answer» E.

Discussion

35.	The unit for inductance is ___________
A.	Ohm
B.	Henry
C.	A/m
D.	A/s
Answer» C. A/m

Discussion

36.	If the current changes from 5A to 3A in 2 seconds and the inductance is 10H, calculate the emf.
A.	5V
B.	10V
C.	15V
D.	20V
Answer» C. 15V

Discussion

37.	If either the inductance or the rate of change of current is doubled, the induced e.m.f?
A.	Remains constant
B.	Becomes zero
C.	Doubles
D.	Becomes half
Answer» D. Becomes half

Discussion

38.	For a coil having a magnetic circuit of constant reluctance, if the flux increases, what happens to the current?
A.	Increases
B.	Decreases
C.	Remains constant
D.	Becomes zero
Answer» B. Decreases

Discussion

39.	As the number of turns in the coil increases, what happens to the inductance of the coil?
A.	Increases
B.	Decreases
C.	Remains the same
D.	Becomes zero
Answer» B. Decreases

Discussion

40.	If the current changes from 3A to 5A in 2s and the emf is 10V. Calculate the inductance.
A.	10H
B.	20H
C.	30H
D.	40H
Answer» B. 20H

Discussion

41.	If the current changes from 5A to 3A in x sec and inductance is 10H. The emf is 10V, calculate the value of x.
A.	2s
B.	3s
C.	4s
D.	5s
Answer» B. 3s

Discussion

42.	Find the value of x if the Mutual inductance is 20H, the inductance of coil 1 is xH and the inductance of coil 2 is 8H. The coupling coefficient is 5.
A.	2H
B.	4H
C.	6H
D.	8H
Answer» B. 4H

Discussion

43.	Find the value of x if the Mutual inductance is x H, the inductance of coil 1 is 2H and the inductance of coil 2 is 8H. The coupling coefficient is 5.
A.	10H
B.	20H
C.	16H
D.	15H
Answer» C. 16H

Discussion

44.	Find the coupling coefficient if the Mutual inductance is 20H, the inductance of coil 1 is 2H and the inductance of coil 2 is 8H.
A.	5
B.	20
C.	2
D.	8
Answer» B. 20

Discussion

45.	In a series circuit, which of the parameters remain constant across all circuit elements such as resistor, capacitor, inductor etc?
A.	Voltage
B.	Current
C.	Both voltage and current
D.	Neither voltage nor current
Answer» C. Both voltage and current

Discussion

Explore topic-wise MCQs in Electrical Engineering.

Find the time taken for the current in an inductor to change to 2A from 0A if the power in the inductor is 5W. The value of inductance is 10H.

If the current in one coil becomes steady, the current in neighbouring coil is?

Calculate the value of emf in an inductor if the value of inductance is 15H and an average current of 5A flows through it in 10s.

Calculate the current in an inductor if the energy stored is 160J and the inductance is 20H.

Practical application of mutual inductance is ____________

The flux linkage in coil 1 is 3Wb and it has x turns and the current in coil 2 is 2A, calculate the value of x if the mutual inductance is 750H.

If the flux linkage in coil 1 is 3Wb and it has 500 turns and the current in coil 2 is 2A, calculate the mutual inductance.

The flux linkage in coil 1 is x and it has 500 turns and the current in coil 2 is 2A, calculate the value of x if the mutual inductance is 750H.

The flux linkage in coil 1 is 3 Wb and it has 500 turns and the current in coil 2 is xA, calculate the value of x if the mutual inductance is 750H.

The types of inductors are ____________

A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the initial value of the current in the circuit.

A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the value of voltage 1s after the switch is closed.

The charging time constant of a circuit consisting of an inductor is the time taken for the current in the inductor to become __________% of the initial current.

A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the initial value of the voltage across the inductor.

What is the energy stored in the magnetic field if the current in a coil has a constant inductance of L henrys grows at a uniform rate?

A coil has a resistance of 4 ohms and an inductance of 2H. It is connected to a 20V dc supply. Calculate the final value of the voltage across the inductor.

Initially, when the switch in a series RL circuit is closed, the current in the inductor is?

Calculate the number of turns in an inductor with a ferromagnetic core when the inductance is 4000 H, the current changes from 5A to 7A and the flux changes from 760 to 800 Wb.

Calculate the change in current in an inductor having inductance 4000H, number of turns is 200 and the flux changes from 760 to 800 Wb.

When a ferromagnetic core is inserted into an inductor, what happens to the flux linkage?

If tan ? = 10 and the resistance is 2 ohm, calculate the inductive reactance.

A laminated steel ring is wound with 200 turns. When the magnetizing current varies between 5 and 7 A, the magnetic flux varies between 760 and 800 Wb. Calculate the inductance of the coil.

Among the following, which is the right formula for inductance of N turns?

For a coil having a magnetic circuit of constant reluctance, the flux is ___________ to the current.

An induced emf is said to be ________

What is the unit for inductive reactance?

If the resistance in a circuit is 2 ohm and the impedance is 20 ohm, calculate the power factor.

If the power factor is 1/10 and the value of impedance is 20 ohm, calculate the resistance in the circuit.

Among the following, which is the right formula for inductance?

Calculate the resistance in an inductive circuit whose time constant is 2s and the inductance is 10H.

Calculate the change in flux of an inductor having inductance 4000 H, number of turns is 200 and the current changes from 5A to 7A.

The charging time constant of a circuit consisting of an inductor is the time taken for the voltage in the inductor to become __________ % of the initial voltage.

Calculate the initial current in an inductor having inductance 4000 H, number of turns is 200 and the flux changes from 760 to 800 Wb. Current changes to 7A.

Calculate the final flux in an inductor having inductance 4000 H, number of turns is 200 and the current changes from 5A to 7A. The initial flux is 760 Wb.

The unit for inductance is ___________

If the current changes from 5A to 3A in 2 seconds and the inductance is 10H, calculate the emf.

If either the inductance or the rate of change of current is doubled, the induced e.m.f?

For a coil having a magnetic circuit of constant reluctance, if the flux increases, what happens to the current?

As the number of turns in the coil increases, what happens to the inductance of the coil?

If the current changes from 3A to 5A in 2s and the emf is 10V. Calculate the inductance.

If the current changes from 5A to 3A in x sec and inductance is 10H. The emf is 10V, calculate the value of x.

Find the value of x if the Mutual inductance is 20H, the inductance of coil 1 is xH and the inductance of coil 2 is 8H. The coupling coefficient is 5.

Find the value of x if the Mutual inductance is x H, the inductance of coil 1 is 2H and the inductance of coil 2 is 8H. The coupling coefficient is 5.

Find the coupling coefficient if the Mutual inductance is 20H, the inductance of coil 1 is 2H and the inductance of coil 2 is 8H.

In a series circuit, which of the parameters remain constant across all circuit elements such as resistor, capacitor, inductor etc?