What is inductance?

When a current flows through a conductor it produces a magnetic field around the conductor. If this induced magnetic field changes with a it produces an electromotive force (EMF) of 1 Volt which opposes the change. Any sudden change is opposed by the induced current. This is known as self -induction.

Inductance: definition, principles and units 

Inductance is the property of an electrical conductor or circuit that causes it to oppose  changes in current. When current flows through a conductor, it creates a magnetic field around it: if the current changes, the magnetic field also changes, which induces an electromotive force, or EMF, that opposes the change in current. This effect is known as self-induction. 

Self-induction and mutual induction 

Whilst self-induction is a product of the cable’s operation, mutual induction is where the effect comes from an outside force. Mutual induction occurs when a changing magnetic field produced by one conductor or coil induces an EMF in another nearby conductor or coil. This principle is used in electrical transformers, where voltage is induced from the primary coil into the secondary coil through a shared magnetic field. 

What is a henry unit? 

The symbol for inductance is L. 

The SI unit of inductance is the henry, represented by the symbol H. One henry is defined as the inductance of a circuit in which an electromotive force of one volt is induced when the current changes uniformly at a rate of one ampere per second. 

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