Revision Quiz on Electromagnetic Induction for JEE & BITSAT Exams

Question 1

In an Electrical Workshop in a college, an AC generator having frequency of 1.5 kHz and a voltage of 240 V was being used. An inductance of L₁= 4 mH is connected across its terminals. Then a second inductance L₂= 5 mH is connected in parallel with it. Then what would be the current that the generator delivers to L₁?

Question 2

The circuit shown consists of a switch (S), a battery (B) of emf E, a resistance R, and an inductor L.

The current in the circuit at the instant the switch is closed is

Question 3

A larger circular coil of N turns and radius R carries a time-varying current

. A small circular coil of n turns and the radius

is placed at the center of the larger coil such that the coils are concentric and coplanar. The induced emf in the small coil is

Question 4

In the circuit shown, initially switch K is closed for long time. At time t = 0, switch K is open. Then total heat produced in resistor R₁ after opening the switch K is –

Question 5

An inductor L and a resistor R are connected in series with a direct current source of emf E. The maximum rate at which energy is stored in the magnetic field is-

Question 6

An insulated wire carrying current in direction as shown on it a conducting loop is kept as shown in the figure (assume no mutual induction). Now if the loop starts rotating find direction of current induced

Question 7

Two similar conducting loops are placed parallel and current in one of them is in clockwise direction as shown in the figure. Which of the following statements is true regarding them?

Question 8

Consider a loop made of conducting material and a bar magnet approaching as shown in the figure. Magnet is moving towards loop in a retarding motion. Find the direction of induced current in the loop. v represents velocity and a represents acceleration at that particular instant

Question 9

A circular loop of wire is in the same plane as an infinitely long wire carrying a constant current

Four possible motions of the loop are marked by N, E, W, and S as shown.

A clockwise current is induced in the loop when the loop is pulled towards

Question 10

A rectangular loop ABCD being pulled out of a uniform magnetic field with uniform velocity

by applying an external force

. Length and breadth of the rectangular loop are

and

, respectively. The total resistance of the loop is

. If the induced current in the loop is 5 mA, then find the magnitude of magnetic field.

Question 11

A wheel with 100 metallic spokes, each 1.0 m long, is rotated with an angular speed

, and in-plane normal to the earth's magnetic field. If the magnitude of the field is

. What will be the emf induced (in μV) between the axle and rim of the wheel?

Question 12

A small conducting loop of radius a and resistance r is pulled with velocity V perpendicular to a long straight conductor carrying current

. If a constant power P is dissipated in the loop, find the variation of the velocity of the loop as a function of x. Given x >> a

Question 13

A coil of cross-sectional area A having n turns is placed in a uniform magnetic field B. When it is rotated with an angular velocity ω, the maximum e.m.f. induced in the coil will be :

Question 14

A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic field B. At the position MNQ, the speed of the ring is v and the potential difference across the ring is

Question 15

Two insulating plates are both uniformly charged in such a way that the potential difference between them is V₂ – V₁ = 20 V. (i.e. plate 2 is at a higher potential). The plates are separated by d = 0.1 m and can be treated as infinitely large. An electron is released from rest on the inner surface of plate 1. What is its speed when it hits plate 2 ?
(e = 1.6 × 10^-19C, m_e = 9.11 × 10^-31 kg)