. Circuit for the measurement of resistance by potentiometer is shown
The galvanometer is first connected at point A and zero deflection is observed at length PJ = 10 cm. In second case it is connect at point C and zero deflection is observed at a length 30 cm from P. Then the unknown resistance X is
Sol: In potentiometer wire potential difference is directly proportional to length.
Let potential drop unit length a potentiometer wire be K.
For zero deflection the current will flow independently in two circles