• # question_answer 34) In a potentiometer experiment two cells of emf ${{E}_{1}}and\text{ }{{E}_{2}}$ are used in series and in conjunction and the balancing length is found to be 58 cm of the wire. If the polarity of ${{E}_{2}}$ is reversed, then the balancing length becomes 29 cm. The ratio ${{E}_{1}}/{{E}_{2}}$ of the emfs of the two cells is- A) 1 : 1                 B) 2 : 1C) 3 : 1                             D) 4 : 1

${{E}_{1}}+{{E}_{2}}=k{{\ell }_{1}}$ ${{E}_{1}}-{{E}_{2}}=k{{\ell }_{2}}$