Coulomb's Law

Coulomb's Law Two Particles

Below is a simulation of Coulomb's Law or the Electrostatic Force in a 2D plane. In the simulation, you can input the positions of two particles as well as the charges whether that be positive or negative of the particles. This is a force of both attraction and repulsion which is then calculated within the simulation. You can also see the radial distance between the particles as well as the directions of the force vectors depending on if the particles are attracting or repelling each other.

Radius:
Vectors:

Position of particle 1:
Position of particle 2:
Charge of particle 1:
Charge of particle 2:

Coulomb's Law states that the magnitude of the attractive and repulsive electrostatic force between particles is directly proportional to the product of the magnitudes of their charges and inversely proportional to the squared distance between them.

This force is known as the electrostatic force, and is defined as F_e = ^{k q₁ q₂}⁄_r² .

\[ F_e = \frac{k \cdot q_1 \cdot q_2}{r^2} \]

k is the electrostatic constant, Coulomb's constant, or the constant of proportionality which is equal to 8.99 × 10^{9 N m2}⁄_C² . It is a proportionality constant that depends on the system of units used in the equation.

q₁ & q₂ represent the two charged particles with a positive or negative charge that are multiplied together.

r is the radial distance between the two charged particles. It is squared because for the positive charge, the lines of force spread out radially in all directions over an increasing area. This increasing area corresponds to the square of the increasing radial distance, which is why the square of the radius is used instead of the radius alone.

With all of these terms combined we get the formula for calculating the electrostatic force.

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