Two thin wire rings each having radius R are placed at distance d apart with their axes coinciding. The charges on the two are `+Q` and `-Q`. The potential difference between the centre so the two rings is

Options

A. `(Q.R)/(4piepsilon_(0)d^(2))`
B. `(Q.R)/(2piepsilon_(0))((1)/(R)-(1)/(sqrt(R^(2)+d^(2))))`
C. `(Q.R)/(4piepsilon_(0))((1)/(R)-(1)/(sqrt(R^(2)+d^(2))))`
D. `0`

Answer

2

Explanation

`E=(1)/(4piepsilon_(0))(qsinpi//2)/(r^(2)pi//2)`
`E=(qsin pi//2)/(2pi^(2) epsilon _(0) r^(2)) (-overline(j))`