What are the universal forces?

There are four fundamental forces (also known as universal forces). They are the strong nuclear, electromagnetic, weak nuclear, and gravitational forces. Each force has a force carrying particle: the gluon (strong nuclear), the photon (electromagnetic), the boson (weak nuclear), and the graviton (gravitational).

The strong nuclear force holds quarks together to form protons and neutrons. The electromagnetic force holds electrons in orbit around an atom's nucleus and also gives matter its rigidity. The weak nuclear force is responsible for emission of beta particles in radioactive decay. The gravitational force also holds matter together, but it is so weak that its effect is only noticible when large masses are involved (e.g., the Earth's gravity holding you on the ground).

Physicists are trying to unify all the forces into one. James Maxwell unified the electrical and magnetic forces into the electromagnetic force. Actually, the electromagnetic and the weak forces have been unified into what is called the electroweak force.

Fundamental Forces

Name Relative
Strong 1 2x10-15 Gluon
Electromagnetic 10-3 infinity Photon
Weak 10-16 10-18 Boson
Graviational 10-41 infinity Graviton

Submitted by Angela (Philippines)
(October 16, 1997)

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