Question

A battery of emf $E_0=12$ V is connected across a 4m long uniform wire having resistance $4\Omega /m$. The cells of small emf’s ${ϵ}_1=2V$ and ${ϵ}_2=4V$ having internal resistance $2\Omega$ and $6\Omega$ respectively, are connected as shown in the figure. If galvanometer shows no deflection at the point N, the distance of point N from the point A is equal to

• A. $\frac{1}{6}m$
• B. $\frac{1}{3}m$
• C. $125cm$
• D. $50cm$

Answer 1

The correct option is C $125cm$

$\frac{E_1{r}_2+E_2{r}_1}{r_1+r_2}=2.5V$
$E=\frac{V}{L}l$