Question

Two charged particles repel each other with a force F. If the charge of both particles is tripled and the distance between them is also tripled, then the force will be

Answer 1

Answer:

The force will not change

Explanation:

The electrostatic force between two charges is given by Coulomb's law:

$F=k\frac{q_1q_2}{r^2}$

where

k is the Coulomb's constant

q1, q2 are the two charges

r is their separation

In this problem:

- Each charge is tripled in magnitude, so

$q_1' = 3q_1\\q_2' = 3q_2$

- The distance is also tripled:

$r'=3 r$

Substituting into the original equation, the new force will be

$F' = k \frac{q_1' q_2'}{r'^2}=k\frac{(3q_1)(3q_2)}{(3r)^2}=k\frac{q_1q_2}{r^2}$

So, the force has not changed.