Two identical conducting spheres, having charges of opposite sign, attract each other with a force of $0.108$ $N$ when separated by $0.5$ $m$. The spheres are connected by a conducting wire, which is then removed, and thereafter, they repel each other with a force of $ 0.036$ $N$. The initial charges on the spheres are

  • A

    $\pm 5 \times 10^{-6}\  C $ and $ \mp  15 \times 10^{-6}\  C$

  • B

    $\pm 1.0 \times 10^{-6}\  C $ and $\mp  3.0 \times 10^{-6}\  C$

  • C

    $\pm 2.0 \times 10^{-6}\  C $ and $\mp 6.0 \times 10^{-6}\  C$

  • D

    $\pm 0.5 \times 10^{-6}\  C$ and $\mp  1.5 \times 10^{-6}\  C$

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