Question

The electrostatic force between two charged metal spheres is 2N. If the charge on each sphere is doubled, what is the new force between the spheres?

Question 2 options:
A. 2N
B. 4N
C. 1N
D. 8

Answer 1

8 N

Step-by-step explanation:

The force between two charges is given by :

`F=(kq_1q_2)/(d^2)`

Where

k is electrostatic constant

d is the distance between two charges

It means,

`F\propto (1)/(d^2)`

When the distance is d, the force is 2 N. If the charge on each sphere is doubled, q₁' = q₂' = 2q₁ = 2q₂. New force will becomes:

`F'=(kq_1'q_2')/(d^2)\\\\F'=(k2q_1* 2q_2)/(d^2)\\\\F'=4* (kq_1q_2)/(d^2)\\\\F'=4* 2\\\\F'=8\ N`

So, the new force becomes 8N. Hence, the correct option is (d).