Question

Two insulated charged copper spheres A and B have their centres separated by a distance of 50 cm. What is the mutual force of electrostatic repulsion if the charge on each `6.5xx10^(-7) C`? The radii of A and B are negligible compared to the distance of separation.

Answer 1

Given, `q_(A)=6.5xx10^(-7)C, q_(B)=6.5xx10^(-7) C`
`r=AB=50cm =50xx10^(-2) m`
`F=1/(4pi epsi_(0)) (q_(A) q_(B))/r^(2)=(9xx10^(9)xx6.5xx10^(-7)xx6.5xx10^(-7))/((50xx10^(-2))^(2))`
`=(9x6.5xx6.5xx10^(-5))/(50xx50xx10^(-4))=1.521xx10^(-2) N`