Electric Induction Coil (Ruhmkorff’s Coil)

Ruhmkorff’s Coil

In the Ruhmkorff’s coil the magnetic field does not change in a sinusoidal manner as in the common coils, but it changes extremely rapidly (essentially collapses very rapidly) so that the secondary generates a voltage near 50000 Volts resulting in spark production.

This is why it is also known as a spark plug coil.

The device operates with 220V AC power and the spark that can be produced is 25-100mm long.