Two concentric spherical shells have charges `+q` and `-q` as shown in figure. Choose the correct options.

Options

A. At a electric field is zero but electric potentiasl in non zero
B. At B electic feid and electric potential both are non zero
C. At C electric field is Zero but electric potential is non zero
D. At C electrilc fiedl and electric potential both are zero

Answer

A, B, D

Explanation

`E=(kq_("in"))/r^2` (Here `k=1/(4piepsilon_0)`
`:. E_A=E_c=0`
but, `E_B!=0`
`V=(kq)/R (rleR)`
`V=(kq)/r(rgeR)`