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.
| Name | Relative Strength |
Range (meters) |
Particle |
|---|---|---|---|
| Strong | 1 | 2x10-15 | Gluon |
| Electromagnetic | 10-3 | infinity | Photon |
| Weak | 10-16 | 10-18 | Boson |
| Graviational | 10-41 | infinity | Graviton |
(October 16, 1997)
Last modified prior to September, 2000 by the Windows Team
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