The two thin coaxial rings, each of radius $'a'$ and having charges $+{Q}$ and $-{Q}$ respectively are separated by a distance of $'s'.$ The potential difference between the centres of the two rings is :
The two thin coaxial rings, each of radius $'a'$ and having charges $+{Q}$ and $-{Q}$ respectively are separated by a distance of $'s'.$ The potential difference between the centres of the two rings is :
- [JEE MAIN 2021]
- A
$\frac{{Q}}{2 \pi \varepsilon_{0}}\left[\frac{1}{{a}}+\frac{1}{\sqrt{{s}^{2}+{a}^{2}}}\right]$
- B
$\frac{{Q}}{4 \pi \varepsilon_{0}}\left[\frac{1}{{a}}+\frac{1}{\sqrt{{s}^{2}+{a}^{2}}}\right]$
- C
$\frac{{Q}}{4 \pi \varepsilon_{0}}\left[\frac{1}{{a}}-\frac{1}{\sqrt{{s}^{2}+{a}^{2}}}\right]$
- D
$\frac{{Q}}{2 \pi \varepsilon_{0}}\left[\frac{1}{{a}}-\frac{1}{\sqrt{{s}^{2}+{a}^{2}}}\right]$
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