$$F=k\frac{|q_1q_2|}{r^2}$$
Where:
- $$F$$ is the electrostatic force between the two charges, measured in newtons (N).
- $$k$$ is the electrostatic constant, approximately 8.988 × 10^9 N m^2 / C^2.
- $$|q_1|$$ and $$|q_2|$$ are the magnitudes of the charges of the two particles, measured in coulombs (C).
- $$r$$ is the distance between the two charges, measured in meters (m).
This equation shows that the electrostatic force between two charges is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them. If either charge is negative, the force will be attractive, and if both charges are positive or negative, the force will be repulsive.
