Clock face rule:
This rule is used to determine the polarity of two faces of a current-carrying circular coil.
According to clock face rule, if we look at one face of the coil through which a current is passing, we have following conclusions:
1. If the current around the face of the coil flows in clockwise direction, that face of the coil will be south pole.
2. If the current around the face of the coil flows in anticlockwise direction, that face of the coil will be north pole.