Question

The electric field lines for a system of two charges $Q_1$ and $Q_2$ fixed at two different points on the $\text{x-}$axis are as shown in the figure. Then $\frac{Q_1}{Q_2}$ might be

• A. $\frac{9}{13}$
• B. $\frac{13}{9}$
• C. impossible to determine
• D. $1$

Answer 1

The correct option is B $\frac{13}{9}$

As we know that, number of electric field lines going out or coming in a charge is directly proportional to the magnitude of that charge, $Q$.

Hence, we can write,

$\frac{Q_1}{Q_2}=\frac{\left(\text{no. of electric field line going out at}{Q}_1\right)}{\text{(no. of electric field line coming in at}{Q}_2)}$

$\therefore \frac{Q_1}{Q_2}=\frac{13}{9}$

Hence, option (a) is correct answer.