Inductors pass DC and block high frequency AC signals.
Inductance is measured in Henries. XL = 2 π F L
Inductors are somewhat like flywheels. You'd not want to stop a flywheel suddenly!
When a current flows, a magnetic field is produced.
Energy is stored in this magnetic field.
Coils act as electromagnets.
Adding an iron core greatly increases this effect.
The stored magnetic energy makes the current in an inductor change slowly unless there are very large voltages.
Suddenly changing the current in an inductor causes a potentially dangerous Back EMF
Inductor switching circuits should include a Back EMF Diode to allow the inductor current to die away slowly.
Electric Fences use Inductors to Generate the High Voltage Pulses
An Induction Coil Producing Sparks
Home Made Electric Fence - Do Not Try This!
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