MCQs of Electromagnetic Induction

Electromagnetic Induction MCQs

MCQs of Electromagnetic Induction

Showing 31 to 40 out of 113 Questions

31.

The phase difference between the flux and the induced emf of the coil rotating perpendicular to the magnetic field is _____

(a)	0 rad
(b)	$\frac{π}{4}$ rad
(c)	$\frac{π}{2}$ rad
(d)	$π$ rad

32.

' ε'

in induced emf

ε = - \frac{d ϕ}{d t}

is _____

(a)	average value
(b)	r.m.s. value
(c)	maximum value
(d)	instantaneous value

33.

A conducting circular loop is expanding in a magnetic field of 2T uniformly so that rate of increase of its radius R is 1 cm/s. Find the induced emf in the loop when its radius is 20 cm. The field is perpendicular to the plane of the loop.

(a)	0.2π × 10^-2 V
(b)	0.8π × 10^-2 V
(c)	2.0 V
(d)	0.1π × 10^-2 V

34.

A solenoid 600 mm long has 50 turns on it and its wound on an iron rod 7.5 mm radius. Find the flux through the solenoid when the current in it is 3A. The relative permeability of iron is 600.

(a)	1.66 Wb
(b)	1.66 nWb
(c)	1.66 mWb
(d)	1.66 µWb

35.

When the rate of change of current is unity, induced emf is equal _____

(a)	thickness of coil
(b)	no. of turns of the coil
(c)	self-inductance
(d)	total flux linked with the coil

36.

A car moves on a plain road. The induced emf in the axle connecting the two wheels is maximum when it moves _____

(a)	East-word at the equator
(b)	West-word at the equator
(c)	East-word at the latitude of 45⁰
(d)	At the poles in any direction

37.

According to the Faraday's law of electromagnetic induction _____

(a)	electric field is produced due to the change in magnetic flux with time.
(b)	magnetic flux is produced due to the change in electric field.
(c)	magnetic field is associated with moving charge.
(d)	none of the above.

38.

Eddy currents are produced, when _____

(a)	by heating the metal
(b)	a metal is kept in varying magnetic field.
(c)	a metal kept in electric field.
(d)	a metal kept in steady magnetic field.

39.

When the current in the coil increases, the direction of emf is _____ to the direction of electric current.

(a)	similar
(b)	perpendicular
(c)	opposite
(d)	none of these

40.

A unit of self-inductance to the resistance of a coil is _____

(a)	second
(b)	ampere
(c)	volt
(d)	weber

Showing 31 to 40 out of 113 Questions