MCQs of Electromagnetic Induction

Electromagnetic Induction MCQs

MCQs of Electromagnetic Induction

Showing 71 to 80 out of 113 Questions

71.

When a wire loop is rotated in a magnetic field, the direction of induced emf changes in energy _____

(a)	1 revolution
(b)	$\frac{1}{2}$ revolution
(c)	$\frac{1}{4}$ revolution
(d)	2 revolution

72.

X and Y two metallic coils are arranged in such a way that when steady change in current flowing X-coil 4A, change in magnetic flux associated with coil Y is 0.4 Wb. Mutual inductance of the system of these coil is _____ H.

(a)	0.2
(b)	5
(c)	0.8
(d)	0.1

73.

In a uniform magnetic field of inductance B a wire in the form of a semicircle of radius r rotates about the diameter of the circle with angular frequency

ω

. The axis of rotation is perpendicular to the field. If the total resistance of the circuit is R, the mean power generated per period of rotation is _____

(a)	$\frac{B π r^{2} ω}{2 R}$
(b)	$\frac{{(B π r^{2} ω)}^{2}}{8 R}$
(c)	$\frac{{(B π r ω)}^{2}}{2 R}$
(d)	$\frac{{(B π r ω)}^{2}}{8 R}$

74.

Which of the following units denotes the dimension

M^{1} L^{2} Q^{- 2}

? (where Q denotes the electric charges)

(a)	$\frac{H}{m^{2}}$
(b)	Wb
(c)	$\frac{W b}{m^{2}}$
(d)	H (Henry)

75.

Radius of a conducing wire r and its plane is perpendicular to magnetic field B. If the conductors is stretched and made in shape of square in its plane and in time t, then induced a emf

ε

is _____

(a)	$\frac{π B r^{2}}{t} (1 - \frac{π}{10})$
(b)	$\frac{π B r^{2}}{t} (1 - \frac{π}{8})$
(c)	$\frac{π B r^{2}}{t} (1 - \frac{π}{6})$
(d)	$\frac{π B r^{2}}{t} (1 - \frac{π}{4})$

76.

If wire of length l is moving in the uniform magnetic field B with velocity v then induced current in the wire is I _____ the resistivity of the wire is , area of cross section is A and

θ

angle between

\vec{v}

and

\vec{B}

(a)	$\frac{B v A \sin θ}{δ}$
(b)	$\frac{B v A \sin θ}{δ}$
(c)	$\frac{B v A \sin θ}{δ}$
(d)	$\frac{B v A \sin θ}{δ}$

77.

A conducting coil having 500 turns has across sectional area 0.15m2. A magnetic field of strength 0.2 T linked perpendicular to this area changes to 1.0 T in 0.4 sec. The induced emf produced in the coil will be _____ volt.

(a)	10.0
(b)	15.0
(c)	75.0
(d)	150.0

78.

A rod of 10 cm is moving perpendicular to uniform magnetic field of intensity 5 × 10^-4 Wb/m². If the acceleration of the rod is 5 m/s², then the rate of increase of induced emf is _____

(a)	2.5 × 10^-4 Vs^-1
(b)	25 × 10^-4 Vs
(c)	20 × 10^-4 Vs
(d)	20 × 10^-4 Vs^-1

79.

The dimensional formula for self inductance is ____

(a)	M¹L²T^-2A^-2
(b)	M¹L²T²A^-2
(c)	M¹L²T^-2A²
(d)	M¹L¹T²A^-2

80.

Self inductance of straight conducting wire is _____

(a)	zero
(b)	infinity
(c)	very large
(d)	very small

Showing 71 to 80 out of 113 Questions