The radii of two concentric spherical conducting shells are `r_(1) and r_(2)(gt r_(1))`. The change on the oute shell is q. The charge on the inner shell which is connected to the earth is

Options

A. `(-r_(2))/(r_(1))`
B. zero
C. `(-r_(1))/(r_(2))q`
D. `-q`

Answer

C

Explanation

Let the charge on the inner shell be q'
The total charge will be zero
`"So, "(kq')/(r_(1))+(Kq)/(r_(2))=0" "(because r_(2) gt r_(1))`
`rArr" "q'=-(Kq//r_(2))/(k//r_(1))`
`=-((r_(1))/(r_(2)))q`