Self Inductance - Definition and Formula

Self Inductance - Definition and Formula

In this post, we will cover Self Inductance Definition and Self Inductance Formula that will help you to understand Self Inductance better.

Self Inductance Definition-

When a coil carries a current it establishes a magnetic flux. When the current in the coil changes, the magnetic flux linking with the coil also changes. It is observed that this change in the value of current or flux in the coil is opposed by the instantaneous induction of opposing emf. This property of the coil by which it opposes the change in the value of current or flux through it due to the production of self-induced emf is called Self-inductance. It is measured in terms of co-efficient of self-inductance L. It obeys Faraday's law of electromagnetic induction like any other induced emf.

Self Inductance Definition

Self Inductance Formula-

For a given coil (provided no magnetic material such as iron is nearby) the magnetic flux linked with it will be proportional to the current, i.e.

where L is called the self-inductance (or simply inductance) of the coil. The induced emf is given by-
Self Inductance Formula

Unit of Self Inductance-

The SI unit of inductance is henry (symbol H), henry is a big unit of inductance, Smaller units millihenry (mil) and microhenry (pH) are used.

Thus, the self-inductance of a coil is 1 H if an induced emf of 1 volt is set up when the current in the coil changes at the rate of one ampere per second.

The role of self-inductance in an electrical circuit is the same as that of the inertia in mechanical motion. Thus the self-inductance of a coil is a measure of its ability to oppose the change in current through it and hence is also called electrical inertia

You May Also Like-


Post a Comment

Join Us on Telegram

Join Us on Telegram
Click on Image

Join Us On Facebook

Popular Posts


ElectricalNotes4u is a Blog for Electrical Engineering Students who want to learn Electrical Engineering online. We will Provide You Notes on all Major subject of electrical engineering. We also Provide Important MCQ that will help you to Prepare for Competitive Exam.