Sensitivity of Potentiometer
A potentiometer is sensitive if:
1. It is capable of measuring very small potential difference.
2. It shows a significant change in balancing length for a small change in the potential difference being measured. The sensitivity of a potentiometer depends upon the potential gradient along the wire. Smaller the potential gradient, greater will be the sensitivity of the Potentiometer.
The sensitivity of potentiometer can be increased by reducing the potential gradient. This can be done in two ways:
1. For a given potential difference, the sensivity can be increased by the increasing the length of the potentiometer wire.
2. For a potentiometer wire of fixed length, the potential gradient can be decreased by reducing the current in the circuit with the help of a rheostat. When in primary circuit current decreases then potential difference across the wire decreases so that without changing in primary circuit for reducing potential gradient the total length of the wire increases.
Graph between V and L
∵ The slope of graphical line
