Coulombs Laws

Coulomb’s Laws express the fundamental relationship between electric charge, force and attraction. They are also known as the Electrostatic Laws and define the electic force.

First Law

Like charges of electricity repel each other. Unlike charges attract each other.

Within the atom we see this at work in the way that negatively charged electrons are attracted to the positively charged nucleus. This attractive force is balanced by the centrifugal force caused by the electron’s rotation around the nucleus. This keeps the electrons in orbit. Without it, they would spiral into the nucleus.

Within circuits, the first law dictates the movement of charge from negatively charged atoms to positively charged atoms through the conductor.

Second Law

The attraction or repulsion between charges acts along the line between the two charges.

Third Law

The size of the electric force varies inversely as the square of the distance between the two charges. Thus if the distance between the two charges is doubled, the attraction or repulsion becomes weaker, decreasing to a quarter of the original value.

Fourth Law

The size of the electric force is proportional to the value of each charge measured in coulombs.