Inductors

The magnetic field formed by a current carrying wire can be made stronger by:

Winding the wire into a coil

If the coil is wound onto a ferrous(iron) core:

The magnetic field around the coil becomes even stronger, since magnetic lines of force travel more easily through air

When current first flows through a coil:

The magnetic field builds relatively slowly

Magnetic field generates a voltage in the coil that:

Opposes the original current flow, known as counter electromotive force, or counter emf

When the current is cut off:

The magnetic field then collapses, and this collapsing magnetic field generates a voltage in the coil that keeps the current flowing

What is known as self induction?

The resistance to change in current flow in a circuit

Self induction is also a:

Property exhibited by electrical components known as inductors

Inductors resist:

Change in current flow

If current is increasing:

The inductor opposes the increasing by generating a voltage that moves against the applied current

If current decreases:

The inductor uses the magnetic energy in the coil to oppose the decrease and to keep the current flowing

What is induction measured in?

A unit known as Henries(L)

Why do inductors work exactly opposite to capacitors?

In the sense that they allow DC to pass easily, but resist the flow of AC

This resistance to current flow is known as:

Inductive Reactance

What is Inductive Reactance measured in:

Ohms

How can an Inductor increase?

With the increasing frequency of the AC signal

An inductor is:

A passive electrical component that opposes sudden changes in current.