Question

If a charge q is placed at centre of the line joining two equal like charges Q .the system of the will be in equilibium if q=?

Answer 1

Explanation:

At equilibrium, net force will be zero, hence

∴

4πε

0

1

×

(r/2)

2

Qq

+

4πε

0

1

×

r

2

Q

2

=0

4q=−Q or q=−

4

Q