and electric coil
What is an electric coil ?
An electric coil is an electric component that consisting of a circular
( or cylindrical ) winding of electric wire.
Voltage across an insulated electric coil
A voltmeter measures voltage across an insulated coil (outside an
electrical circuit): voltage is zero.
Voltage across an electric coil near a stationary magnet
The voltage across an electric coil located close to a stationnary
magnet remains zero.
Voltage across an electric coil near a moving magnet
As soon as the magnet is moved, a voltage appears across the coil but
the voltage returns to zero when the magnet stops.
This voltage is either positive or negative:
- The sign of the voltage depends on whether the magnet is moving
towards or away from the coil.
- The sign of the voltage also depends on the magnetic pole of the
magnet facing the coil.