The null point of galvanometer is defined as the point at which the galvanometer shows no deflection as there is no flow of current through the galvanometer.

What does null deflection in galvanometer show?

Null deflection point is the point at which the galvanometer shows no deflection. In the potentiometer to get the zero reading in galvanometer joe key is moved along the length of the potentiometer wire. At a particular point the null defection is obtained and that length is known as balancing length.

What happens at null point?

The balancing point or null point of the potentiometer is the point on the slide wire when the galvanometer shows zero deflection. The balance point is found to determine the unknown voltage of the cell connected to the cell.