Question

A potentiometer wire of length 5m is connected to a battery. For certain cell having negligible internal resistance tge null point is obtained at 250cm. If tge length of a wire is increase by 1m, where will be the new null point?

Answer 1

Hey dear,

◆ Answer-
Null point at = 300 cm

◆ Explaination-
Initially length of the wire is 5 m.
At this time, null point is obtained at 250 cm.

Later length of the wire is increased by 1 m. Total length is therefore 5+1 = 6 m.

In potentiometer, Null point is directly proportional to length of wire.

Therefore,
Null point is obtained at 6/5 × 250 = 300 cm.

Hope it helps...