Question

A two-metre potentiometer wire is used in an experiment to determine the internal resistance of a voltaic cell. The e.m.f of the cell is balanced by the fall of potential along 90.6cm of wire. When a standard resistor of 10 0hms is connected across the cell the balance length is found to be 75.5cm . Draw a labelled circuit diagram and
calculate from first principles, the internal resistance of the cell.