Degree of Freedom¶
Defn. 1
The degree of freedom for a dynamic system is the number of directions in which a particle can move freely, or the total number of coordinates required to describe completely the position and configuration of the system. It is denoted by f or N.
Defn. 2
The minimum number of independent coordinates needed to specify the position and configuration of a thermo-dynamical system in space is called the degree of freedom of the system.
Examples¶
- A free particle moving along x-axis needs only one coordinate to specify it completely. So its degree of freedom is one. Similarly, a particle moving over a plane has two degrees of freedom and a particle moving in space has three degrees of freedom.
- A monoatomic molecule has only three translational degrees of freedom.
- At Normal temperature, diatomic molecules have five degrees of freedom and at a very high temperature the diatomic molecules possess additional two degrees of freedom due to vibrational motion.
| Translation DOF | Rotational DOF | Vibrational DOF |
|---|---|---|
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