Two point charges q1 and q2 are 3.00 m apart, and their total charge is 20 μc . (a) if the force of repulsion between them is 0.075n, what are magnitudes of the two charges? (b) if one charge attracts the other with a force of 0.525n, what are the magnitudes of the two charges? note that you may need to solve a quadratic equation to reach your answer.

Explanation:

Let two charges are , such that, .............(1)

Distance between charges, r = 3 m

The force of repulsion between them is, F = 0.075 N

We can consider that both charges are positive, so that there exists the force of repulsion. The force of repulsion is given by :

.............(2)

On solving equation (1) and (2) we get :

(b) Now the force of attractive, F = -0.525 N

Let charges are such that, .............(3)

Force of attraction is given by :

.............(4)

Now on solving equation (3) and (4) we get :

and

Hence, this is the required solution.