Question

We have 3 conducting spheres A,B and C of radius 2R, R and $\frac{R}{2}$ respectively. Out of the 3, A is charged to some charge. Charged sphere A touches B and then both are separated by distance d. Force between A and B is F. Again this sphere B touches C and is separated by distance d from C then force between B and C is

• A. $\frac{F}{9}$
• B. $\frac{F}{8}$
• C. $\frac{F}{6}$
• D. $\frac{F}{2}$

Answer 1

The correct option is A $\frac{F}{9}$


$F=K\frac{\frac{2Q}{3}.\frac{Q}{3}}{d^2}$

$F^{\prime }=K\frac{\frac{2Q}{9}\times \frac{Q}{9}}{d^2}$

$F^{\prime }=\frac{F}{9}$