Self and Mutual Induction

IMPORTANT

Self and Mutual Induction: Overview

This topic covers concepts, such as, Induction, Self Induction, Series Combination of Inductors & Parallel Combination of Inductors etc.

Important Questions on Self and Mutual Induction

EASY
IMPORTANT

The SI unit of coefficient of mutual induction is

EASY
IMPORTANT

The S.I. unit of self-inductance of a coil is 

EASY
IMPORTANT

The circuit arrangement given below shows that when A.C. passes through the coil A, the current starts flowing in coil B.

Question Image

Mention the underlying principle involved.

EASY
IMPORTANT

What is the expression for the self-inductance of a long, air-cored solenoid of length l, radius r, and having N number of turns?

EASY
IMPORTANT

A coil has an inductance of 2 H and resistance of 4 Ω. A 10 V is applied across the coil. The energy stored in the magnetic field after the current has built up to its equilibrium value will be _____ ×10-2 J

EASY
IMPORTANT

A 12 V battery connected to a coil of resistance 6  through a switch, drives a constant current in the circuit. The switch is opened in 1 ms. The emf induced across the coil is 20 V. The inductance of the coil is :

EASY
IMPORTANT

The magnitude of induced e.m.f. in a coil of inductance 1 mH in which a current is changing from 0.1 A to 2.1 A in 0.01 sec is

 

EASY
IMPORTANT

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 I0=10 A and ω=100π rad s-1. The value of maximum induced emf in the second coil is _____ .

EASY
IMPORTANT

An emf induced in a secondary coil is 20000 V when the current breaks in the primary. The mutual inductance is 5 H and the current reaches to zero in 10-4 s in primary. Calculate the maximum current in the primary before the break.

HARD
IMPORTANT

If the difference between the equivalent inductance in the following figures is nL then find the value of n. Given coupling coefficient is C=2 (Where coupling coefficient is defined as C=L1L2M)

Question ImageQuestion Image

 

HARD
IMPORTANT

In a uniform and constant magnetic field of induction B, two long conducting wires ab and cd are kept parallel to each other at distance l with their plane perpendicular to B. The ends a and c are connected together by an ideal inductor of inductance L. A conducting slider wire PQ is imparted a speed v0, at time t=0. The situation is shown in the figure. AT time t=πmL4Bl, the value of current I through the wire PQ is (ignore any resistance, electrical as well as mechanical)

Question Image​​​​​​​

MEDIUM
IMPORTANT

In the figure shown, Vab at t=1 s is

Question Image

HARD
IMPORTANT

The effective inductance between A and B is KL. Determine K?

Question Image​​​​​​​

EASY
IMPORTANT

A mutual inductor consists of two coils X and Y as shown in figure in which one-quarter of the magnetic flux produced by X links with Y, giving a mutual inductance M. What will be the mutual inductance when Y is used as the primary?

Question Image

MEDIUM
IMPORTANT

Two coils are fixed in space at some distance from each other such that there is a flux linkage between them. When coil 1 has no current and the current in the coil 2 increases at the rate 15.0 A s-1, the emf in the coil 1 is 25.0 mV. When coil 2 has a current of 3.6 A, the flux linkage in coil 2 (in mWb) is 

EASY
IMPORTANT

If 0.1 J of energy is stored for the flow of current of 0.2 A in an inductor, then its inductance value is

HARD
IMPORTANT

Two coils are fixed in space at some distance from each other such that there is a flux linkage between them. When coil 1 has no current and the current in the coil 2 increases at the rate 15.0 A s-1, the emf in the coil 1 is 25.0 mV. When coil 2 has a current of 3.6 A, the flux linkage in coil 2 (in mWb) is 

HARD
IMPORTANT

When induced emf in inductor coil is 50% of its maximum value, then stored energy in inductor coil in the given circuit will be (in μJ):

Question Image 

EASY
IMPORTANT

A condenser of capacity 6 μF is fully charged using a 6 V battery. The battery is removed and a resistance less 0.2 mH inductor is connected across the condenser. If the current which is flowing through the inductor (in A) when 13rd of the total energy is in the magnetic field of the inductor is I, what is the value of 10I?

MEDIUM
IMPORTANT

Calculate the self-inductance of a long solenoid having 500 turns, if the flux linked with each turn of the solenoid is 4 × 103 Wb when the current of 2 A passes through it.