Two equal point charges Q are separated by a distance d. One of the charges is released and moves away from the other due only to the electrical force between them. When the moving charge is a distance 3d from the other charge, what is its kinetic energy ?

kinetic energy of charge will be

Explanation:

First calculate the initial potential energy of each charge;

PE1=;

When the charges are at distance of 3d then its potential energy is;

PE2=;

And kinetic energy is equal to difference between their potential energy at two different positions,

So,

K.E=PE1-PE2;

K.E=;

K.E=;

Hence the kinetic energy of charge will be

well clustered together.

points close on a scatter diagram