Electromagnetic Induction  MCQs

MCQs of Electromagnetic Induction

Showing 1 to 10 out of 113 Questions
1.
When electric current in a coil steadily changes from +2 A to -2 A in 0.05 s, an induced emf of 8.0 v is generated in it. Then the self-inductance of the coil is _____ H.
(a) 0.2
(b) 0.4
(c) 0.8
(d) 0.1
Answer:

Option (d)

2.
X and Y coils are joined in a circuit in such a way that when the change of current in X is 2 A , the change in the magnetic flux in Y is 0.4 Wb . The mutual induction of the system of two coils is _____ H.
(a) 0.8
(b) 0.4
(c) 0.2
(d) 5
Answer:

Option (c)

3.
A coil is placed in a time-varying magnetic field. Electrical power is dissipated in the form of Joule heat due to the current induced in the coil. If the number of turns were to be quadrupled and the wire radius halved, the electrical power dissipated would be _____ .
(a) halved
(b) the same
(c) doubled
(d) quadrupled
Answer:

Option (b)

4.
The self-inductance of two solenoids A and B having equal length are same. If the number of turns in two solenoids A and B are 100 and 200 respectively, the ratio of the radii of their cross-section will be _____ .
(a) 2 : 1
(b) 1 : 2
(c) 1 : 4
(d) 4 : 1
Answer:

Option (a)

5.
A coil of surface area 100 cm2 having 50 turns is held perpendicular to the magnetic field of intensity 0.02 Wbm-2 . The resistance of the coil is 2 Ω . If it is removed from the magnetic field in 1 s, the induced charge in the coil is _____ .
(a) 5 C
(b) 0.5 C
(c) 0.05 C
(d) 0.005 C
Answer:

Option (d)

6.
The magnetic flux linked with a coil is changing with time t (second) according to Φ=6t2-5t+1. Where Φ is in Wb. At t = 0.5 s, the induced current in the coil is _____ . (the resistance of the circuit is 10 Ω)
(a) 1 A
(b) 0.1 A
(c) 0.1 mA
(d) 10 A
Answer:

Option (b)

7.
The mutual inductance of the system of two coils is 5 mH. The current in the first coil varies according to the equation I =I0sinωt , where I= 10A and ω = 100π rads-1. The value of maximum induced emf in the second coil is _____ .
(a) 2π V
(b) 5π V
(c) π V
(d) 4π V
Answer:

Option (b)

8.
A magnet is moving towards a coil along its axis and the emf induced in the coil is ε. If the coil also starts moving towards the magnet with the same speed, the induced emf will be _____ .
(a) ε2
(b) ε
(c)
(d)
Answer:

Option (c)

9.
A square conducting coil of area 100 cm2 is placed normally inside a uniform magnetic field of 103 Wbm-2. The magnetic flux linked with the coil is _____ Wb.
(a) 10
(b) 10-5
(c) 105
(d) 0
Answer:

Option (a)

10.
The distance between two extreme points of two wings of an aeroplane is 50 m. It is flying at a speed of 360 kmh-1 in horizontal direction. If the vertical component of earth's magnetic field at that place is 2 × 10-4 Wbm-2 , the induced emf between these two end points is _____ V.
(a) 0.1
(b) 1.0
(c) 0.2
(d) 0.01
Answer:

Option (b)

Showing 1 to 10 out of 113 Questions