Inductance

Inductance:

• A magnetic field is produced when current flows in a coil

• As the magnetic field reverses an induced EMF is created across the coil

• The induced voltage opposes the source voltage

• This counter EMF tries to keep the current from decreasing

• This opposition to current flow is called Induction Reactance and causes the current to lag the voltage

• Know as ELI  in circuit of pure inductance voltage leads current by 90 degrees

Self Inductance:

• When varying lines of magnets flux induce an EMF in a coil has self inductance

Mutual Inductance:

• When varying lines of magnetic flux induce an EMF in an adjacent coil the coils have mutual inductance (transformer)

Inductance opposes any change in circuit