Two identical thin rings, each of radius $R $ meter are coaxially placed at distance $R$ meter apart. If $Q_1$ and $Q_2$ coulomb are respectively the charges uniformly spread on the two rings, the work done in moving a charge $q$ from the centre of one ring to that of the other is
Two identical thin rings, each of radius $R $ meter are coaxially placed at distance $R$ meter apart. If $Q_1$ and $Q_2$ coulomb are respectively the charges uniformly spread on the two rings, the work done in moving a charge $q$ from the centre of one ring to that of the other is
- A
zero
- B
$q$$\,\left( {{Q_1}\, - \,{Q_2}} \right)\left( {\sqrt 2 \, - \,1} \right)/\left( {\sqrt {2\,} \,.\,4\pi {\varepsilon _0}R} \right)$
- C
$q\,\sqrt 2 \,\left( {{Q_1}\, + \,{Q_2}} \right)/4\pi {\varepsilon _0}R$
- D
$q$$\left( {{Q_1}\, - \,{Q_2}} \right)\left( {\sqrt 2 \, + \,1} \right)/\left( {\sqrt 2 \,.4\pi {\varepsilon _0}R} \right)$
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