Answer to Question #189349 in Physics for Paulos

Question

Charge A exerts a force on charge B. Charge A does not change but charge B gets 4× smaller. What happens to the force on charge B?

Your answer

Answer 1

According to the Coulomb's law, the between two point charges is proportional to the product of that charges:

$$F \propto |q_A||q_B|$$

Thus, since the charge B becomes 4 times smaller, the force becomes 4 times smaller as well.

Answer. The force becomes 4 times smaller.