# A potentiometer wire AB having length L and resistance 12 r is joined to a cell D of emf e and internal resistance r. A cell C having emf e/2 and internal resistance 3r is connected. The length AJ at which the galvanometer as shown in fig. shows no deflection is:

Question:

A potentiometer wire AB having length L and resistance $12 \mathrm{r}$ is joined to a cell $\mathrm{D}$ of emf $\varepsilon$ and internal resistance r. A cell $\mathrm{C}$ having $\mathrm{emf} \varepsilon / 2$ and internal resistance $3 \mathrm{r}$ is connected. The length AJ at which the galvanometer as shown in fig. shows no deflection is: 1. $\frac{11}{12} \mathrm{~L}$

2. $\frac{11}{24} \mathrm{~L}$

3. $\frac{13}{24} \mathrm{~L}$

4. $\frac{5}{12} \mathrm{~L}$

Correct Option: 3

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