A potentiometer wire of length L and a resistance r are connected in series with a battery of emf `E_(0)` and resistance `'r_(1)'`. An unknown emf E is balanced at a length 'l' of the potentiometer wire. The emf E will be given by

Options

A. `(E_(0)l)/(L)`
B. `(LE_(0)gamma)/((gamma + gamma_(1))l)`
C. `(LE_(0)gamma)/(l gamma_(1))`
D. `(E_(0)gamma)/((gamma+ gamma_(1)))(l)/(L)`