The wire of a potentiometer has resistance and length

PHYSICS · Single correct · ISC · Physics · Current Electricity · Current Electricity

Problem

The wire of a potentiometer has resistance

4\,\Omega

and length

1\,\mathrm{m}

. It is connected to a cell of emf

2\,\mathrm{V}

and internal resistance

1\,\Omega

. If a cell of emf

1.2\,\mathrm{V}

is balanced by it, the balancing length will be (a)

90\,\mathrm{cm}

(b)

60\,\mathrm{cm}

(c)

50\,\mathrm{cm}

(d)

75\,\mathrm{cm}