Two concentric conducting thin spherical shells A andB having radii rA and `r8 (r_(8) gt r_(A))` are charged to `Q_(A)` and `- Q_(B)(|Q_(B)| gt |Q_(A)|)`. The electric field strength along a line passing through the centre varies with the distance x as :

Options

A.
B.
C.
D.

Answer

C

Explanation

`|Q_(n)|gt|Q_(A)|` (given). Inside the shell B, the potential is a constant and negative.
But `V_(A)" inside "r_(A)` is positive and greater than that of B because `r_(A)ltr_(B)`. Upto `r_(n)` this is `gtV_(n)` one gets the course `prop 1//r.` At B, the negative potential is more therefore the potential line still negative. (c) explains all these factors.
Note: However the question asked is the field and the diagrams given are for the potential. This an error.