Three concentric metallic spherical shells of radii R, 2R, 3R are given charges `Q_(1) Q_(2) Q_(3)`, respectively. It is found that the surface charge densities on the outer surface of the shells are equal. Then, the ratio of the charges given to the shells `Q_(1) : Q_(2) : Q_(3)` is

Options

A. `1:2:3`
B. `1:3:5`
C. `1:4:9`
D. `1:8:18`

Answer

B

Explanation

The charge distribution on the shells outer surface will be
For Shell `1 to Q_(1)`
For shell `2 to Q_(1)+Q_(2)`
For Shell `3 to Q_(1)+Q_(2)+Q_(3)`
`sigma` is same