Question

A charged metallic sphere A having charge qA is brought in contact with an uncharged metallic
sphere of same radius and then separated by a distance d. What is the electrostatic force between
them.

Answer 1

Dear student

$$\begin{gathered} Whenthetwospheresareboughtincontactwitheachotherthandistributionofchargetakesplacetilltheyacquirethesamepotential. \\ Potentialosspherehavingchargeqis \\ V=\frac{1}{4\pi \in }\frac{q}{R} \\ asradiusissamesotheyhavesamepotentialiftheyhevesamecharge.Thatischargeisequallydividedbetweenthem. \\ Chargeoneachballaftertheyareputincontactis=\frac{q}{2} \\ Forcebetweenthem \\ F=\frac{1}{4\pi \in }\frac{{\displaystyle \frac{q}{2}}\times {\displaystyle \frac{q}{2}}}{d^2}=\frac{1}{4\pi \in }\frac{q^2}{4d^2}=\frac{1}{16\pi \in }\frac{q^2}{d^2} \\ Regards \end{gathered}$$