degree of freedom

mechanics

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 26, 2026

Quick Summary

In mechanics, a degree of freedom refers to the number of independent quantities required to describe the state of a system. Think of it as the number of ways a body can move or a system can change.12

For example, a point moving freely in space has three degrees of freedom because three coordinates are needed to pinpoint its location. However, if there are restrictions, like a point needing to stay on a specific path, the degrees of freedom are reduced. A simple pendulum, for instance, only has one degree of freedom because its position is determined by a single value: its angle. In statistics, degrees of freedom relate to the number of independent variables that can vary in a data set.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

muscle
Muscles that work skeletons
…technical terms as allowing one degree of freedom of movement. The human ankle performs two kinds of movement, flexion/extension and inversion/eversion, allowing two degrees of freedom. Ball-and-socket joints, such as the human hip, allow three degrees of freedom. Most animal joints have at least two muscles (an antagonistic pair) for…
Read More
…technical terms as allowing one degree of freedom of movement. The human ankle performs two kinds of movement, flexion/extension and inversion/eversion, allowing two degrees of freedom. Ball-and-socket joints, such as the human hip, allow three degrees of freedom. Most animal joints have at least two muscles (an antagonistic pair) for…
Read More