Question

A potentiometer wire is 4 m long and a potential difference of 3 V is maintained between the ends. The e.m.f. of the cell which balances against a length of 100 cm of the potentiometer wire is ______

Options

• 0.75 V

• 0.25 V

• 0.60 V

• 0.50 V

Answer 1

A potentiometer wire is 4 m long and a potential difference of 3 V is maintained between the ends. The e.m.f. of the cell which balances against a length of 100 cm of the potentiometer wire is 0.75 V.

Explanation:

Potential gradient = `3/4 V/m`

So, emf against 100 cm = `3/4 xx 1 V = 0.75 V`