# Electrostatic Force – Formula – Coulomb’s Law

## Electrostatic Force – Formula – Coulomb’s Law

Forces between static electrically charged particles are governed by the Coulomb’s law. Coulomb’s Law can be used to calculate the force between charged particles (e.g. two protons). The electrostatic force is directly proportional to the electrical charges of the two particles and inversely proportional to the square of the distance between the particles. Coulomb’s Law is stated as the following equation. Both, the Coulomb’s law and the magnetic force, are summarized in the Lorentz force law. Fundamentally, both magnetic and electric forces are manifestations of an exchange force involving the exchange of photons.

The photon, the quantum of electromagnetic radiation, is an elementary particle, which is the force carrier of the electromagnetic force. Photons are gauge bosons having no electric charge or rest mass and one unit of spin. Common to all photons is the speed of light, the universal constant of physics. In empty space, the photon moves at c (the speed of light – 299 792 458 metres per second).

The electromagnetic force plays a major role in determining the internal properties of most objects encountered in daily life. The chemical properties of atoms and molecules are determined by the number of protons, in fact, by number and arrangement of electrons. The configuration of these electrons follows from the principles of quantum mechanics. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. In the periodic table, the elements are listed in order of increasing atomic number Z. In fact, the forces of electric attraction and repulsion of electric charges are so dominant over the other three fundamental forces that they can be considered to be negligible as determiners of atomic and molecular structure.

## Example: Electrostatic Force

Noteworthy, in a four liters of water there is about 2.1 x 108C of total electron charge. Thus, if we place two bottles a meter apart, the electrons in one of the bottles repel those in the other bottle with a force of 4.1 x 1026N. This tremendous force is comparable with the force than the planet Earth would weigh if weighed on another Earth. Ut, as was written, there are also positive (protons) and these charges tend to cancel each other out.

References:
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