Question

The length of a potentiometer wire is `l`. A cell of emf `E` is balanced at a length l/3 from the positive end of the wire. If the length of the wire is increased by l/2. At what distance will the same cell give a balance point.
A. `2l//3`
B. `l//2`
C. `l//6`
D. `4l//3`

Answer 1

Correct Answer - B
`E=x_(1)l_(1)=x_(2)l_(2)`
`(E_(0))/lxxl/(3)=E_(0)/(3l//2)xxl_(2)impliesl_(2)=l/2`