Two charged spherical conductors (each of radius \(\mathrm{R})\) are at a distance \(d\) part \((\mathrm{d} > 2 \mathrm{R})\). The charge on one is \(+q\) and that on the other is \(-q\). The magnitude of the force between them will be :

• A

  \(\frac{1}{4 \pi \varepsilon_0} \frac{\mathrm{q}^2}{\mathrm{~d}^2}\)
• Correct answer
  B

  more than \(\frac{1}{4 \pi \varepsilon_0} \frac{\mathrm{q}^2}{\mathrm{~d}^2}\)
• C

  Less than \(\frac{1}{4 \pi \varepsilon_0} \frac{\mathrm{q}^2}{\mathrm{~d}^2}\)
• D

  zero

Solution

Because of induction, the effective force between them becomes equal to greater than \(\mathrm{F}=\frac{1}{4 \pi \varepsilon_0} \frac{\mathrm{q}^2}{\mathrm{~d}^2}\)

Hence, the correct answer is option: 'B'.