Answer:
5. Quadruple
Explanation:
The electrostatic force between two charged particles is given by:
[tex]F=k\frac{q_1 q_2}{r^2}[/tex]
where
k is the Coulomb's constant
q1, q2 are the two charges
r is the separation between the charges
If the distance between the charges is reduced to half,
[tex]r' = \frac{r}{2}[/tex]
So the new force will be
[tex]F'=k\frac{q_1 q_2}{(r/2)^2}=4(k\frac{q_1 q_2}{r^2})=4F[/tex]
So, the force will quadruple.
