Question

Two spheres of charge 'q' are placed at a
distance 'r' meter apart. If one sphere is
undergoing a circular motion around the other one
at a radius 'r', what will be the work done?​

Answer 1

• Two spheres of charge q are placed at a distance r.
• if one sphere is undergoes a circular motion around other one.
• As the charges attract (or repelled) with a force (F) directed along line joining them.
• Hence work done is zero as

        W=$\int\limits {F} \, dr$ cosθ

        as θ=90°

        W=$\int\limits {F} \, dr$ cos90°

        W=0