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Frequently Asked Questions On Mutual Inductance!

Below is a set of frequently asked questions and important information on mutual inductance. The answers to the questions mentioned in the end will help understand the topic in detail.

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Motors, generators, and transformers have their principle operating system based on mutual inductance. The wide range of applications of mutual inductance makes it one of the most important topics to study in the subject of Physics. Mutual inductance helps to study and understand the working principle and systems of numerous electrical devices. The principle of mutual inductance is also used by various electrical devices that consist of components interacting with magnetic fields working on the same principle.

Below is all you need to know about mutual inductance and some of the most frequently asked questions on this crucial topic.

What is Mutual inductance?

When two coils are brought close to one another, then one of these coils resists or opposes the change in current in the neighboring or the other coil. When the change in current is observed in the other coil. Flux gets set up in the coil. Eventually, this results in inducing changing flux EMF in the coil. This EMF is known as the mutually induced EMF, and this entire phenomenon is known as mutual inductance.

The concept of mutual inductance can be understood deeply with the help of taking an example of two coils- Coil A and Coil B. Now, suppose Coil A and Coil B are close to each other. Then, when current flows in the coil by closing the switch S, flux φ gets set up, and an emf is induced in Coil A. Now, if by changing the resistance R, the value of current is changed in Coil A, then this changing current results in changing the flux linking with Coil B.

The SI unit of mutual inductance, Henry, is named after an American scientist Joseph Henry. Joseph Henry was the scientist who explained the concept of two coils. The unit of MI also qualifies as the most frequently asked question on mutual inductance.

1Henry= 1 Tesla . 1 m²/ 1 Ampere

What are some common applications of mutual inductance?

Frequently asked questions on mutual inductance often include questions on its applications. Below are some of the most common applications of mutual inductance.

Generators
Motors
Transformers
Digital signal processing
Electrical devices working on the magnetic field principle
Used in Eddy currents calculation

What are the factors affecting mutual inductance?

Inner coil’s area
The magnetic permeability of the medium inside the primary coil
Length of the primary coil
The separation between the coils
Number of turns in the coils

Mutual inductance between two coaxial solenoids

Most examples of frequently asked questions often include at least one question regarding the calculation of MI between two coaxial solenoids.

Two solenoids S1 (inner solenoid) and S2 (outer solenoid) are considered. S2 has N2 number of turns and its radius is taken as r2 while for S1 the radius is r1 and the number of turns is equal to N1. The lengths of both these solenoids are considered to be equal.

When current I2 passes through S2 , magnetic induction is represented by

Conclusion

Mutual inductance, the working principle of numerous electrical devices, is a property of a conductor or a coil in the circuit. It is defined as the property of a conductor of a coil or conductor that opposes the change in current or voltage in another coil placed close to it. Most examples of frequently asked questions include questions based on mutual inductance due to the topic’s significance and the wide range of applications of this principle. Mutual inductance is the basic functional principle of some of the most used electrical devices, such as transformers, generators and motors.