The basic forces in nature
Contemporary Physics Education Project

# Fundamental Forces

The interactions in the Universe are governed by four forces (strong, weak, electromagnetic and gravitational).

Physicists are trying to find one theory that would describe all the forces in nature as a single law. So far they have succeeded in producing a single theory that describes the weak and electromagnetic forces (called electroweak force). The strong and gravitational forces are not yet described by this theory.

FUNDAMENTAL FORCES

Interaction Relative Strength Range Mediating Particle
Strong 1 Short Gluon
Electromagnetic 0.0073 Long Photon
Weak 10-9 Very Short W,Z
Gravitational 10-38 Long Graviton

## Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

## Neutrinos

The neutrino is an extremely light particle. It has no electric charge. The neutrino interacts through the weak force. For this reason and because it is electrically neutral, neutrino interactions with...more

## Tools for Math and Science

Some ideas are used throughout the sciences. They are "tools" that can help us solve puzzles in different fields of science. These "tools" include units of measurement, mathematical formulas, and graphs....more

## Mechanics

Mechanics is the term used to refer to one of the main branches of the science of physics. Mechanics deals with the motion of and the forces that act upon physical objects. We need precise terminology...more

## Fundamental Forces

The interactions in the Universe are governed by four forces (strong, weak, electromagnetic and gravitational). Physicists are trying to find one theory that would describe all the forces in nature as...more

## Creating Elements up to Iron

When the temperature in the core of a star reaches 100 million degrees Kelvin fusion of Helium into Carbon occurs. Oxygen is also formed from fusion of Carbon and Helium together when the temperature is...more

## Binding Energy

A plot of the binding energy per nucleon vs. atomic mass shows a peak atomic number 56 (Iron). Elements with atomic mass less then 56 release energy if formed as a result of a fusion reaction. Above this...more

## Fusion Experiments

There are several experiments where nuclear fusion reactions have been achieved in a controlled manner (that means no bombs are involved!!). The two main approaches that are being explored are magnetic...more

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