Question

A charge of $5\mu\text{C}$ is placed at the center of a spherical shell $S_1$ of radius $10\text{ cm}$. Now this system is enclosed inside another spherical shell $S_2$ of radius $20\text{ cm}$. The ratio of the electrical flux through the surface $S_2$ to $S_1$ is:

• A. $1:1$
• B. $4:1$
• C. $2:1$
• D. $1:2$

Hint:

Electric flux measures the total number of electric field lines passing through a surface. Every single field line originating from the central charge that cuts through the inner shell $S_1$ must continue outward and cut through the outer shell $S_2$ as well. Since the line count is identical, the flux ratio must be $1:1$.

Answer 1

The Correct Option is A