Electromagnetic Induction  MCQs

MCQs of Electromagnetic Induction

Showing 91 to 100 out of 113 Questions
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91.
A rod of 10 cm length 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 e.m.f. is _____.
(a) 2.5 × 10-4 Vs-1
(b) 20 × 10-4 Vs
(c) 25 × 10-4 Vs
(d) 20 × 10-4 Vs-1
Answer:

Option (a)

92.
Select incorrect unit of self inductance _____.
(a) WeberAmpere
(b) Volt - SecondAmpere
(c) mho - second
(d) ohm - second
Answer:

Option (b)

93.
In an electromagnetic induction, the induced emf in a coil does not depend on _____.
(a) change in the flux
(b) time
(c) resistance of the circuit
(d) None of the above
Answer:

Option (c)

94.
A coil of 40 H inductance is connected in series with a resistance of 8 ohm and the combination is joined to the terminals of a 2 V battery. The time constant of the circuit is _____.
(a) 440 s
(b) 20 s
(c) 5 s
(d) 15 s
Answer:

Option (c)

95.
1 tesla = _____ gauss
(a) 10-4
(b) 10-8
(c) 104
(d) 106
Answer:

Option (c)

96.
The magnetic flux linked with a coil varies with time as Φ(t) = 3 t2 + 4 t + 9 Wb. The magnitude of induced emf at t = 2 s is _____ volt.
(a) 4
(b) 8
(c) 12
(d) 16
Answer:

Option (d)

97.
Lenz's law is statement of _____.
(a) law of conservation of charge
(b) law of conservation of current
(c) law of conservation of energy
(d) law of conservation of momentum
Answer:

Option (c)

98.
The flux linked with coil at any instant 't' is given by Φ(t) = 10 t2 - 50 t + 100 Wb. Then induced emf E at t = 3 s is _____ volt.
(a) 10
(b) -10
(c) 20
(d) -30
Answer:

Option (b)

99.
When a coil of metal wire is kept in a non-uniform magnetic field, _____.
(a) an emf and current both are induced in the coil
(b) a current but not emf is induced in the coil
(c) an emf but no current is induced in the coil
(d) neither current nor emf is induced in the coil
Answer:

Option (d)

100.
A magnetic wire of length 1.0 m moves with a speed of 10 ms-1 perpendicular to a magnetic field. If the emf induced in the wire is 1.0 V, the magnitude of magnetic field is _____ T.
(a) 0.01
(b) 0.02
(c) 0.1
(d) 0.2
Answer:

Option (c)

Showing 91 to 100 out of 113 Questions
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