Question

What is the force between two equal charges each one has magnitude of 5 x 10 ^-8 C if they are .05 m apart?

Answer 1

Answer:

Let the charge q be placed at 0, so that its distance from charge at A=x and from charge B=r−x.

Now, the system is in equilibrium, if electrostatic force on q due to charge at A= electrostatic force on q due to charge at B ie,

4πε

0

1

x

2

qQ

=

4πε

0

1

(r−x)

2

qQ

(r−x)

2

=x

2

or x=

2

r

Three charges will be in equilibrium if net force on each charge is zero i.e,

4πε

0

1

(

2

r

)

2

qQ

+

4πε

0

1

r

2

Q−Q

=0

or, q=

4

−Q