Moment of Inertia
In classical mechanics, moment of inertia, also called mass moment, rotational inertia, polar moment of inertia of mass, or the angular mass, (SI units kg·m²) is a measure of an object's resistance to changes to its rotation. It is the inertia of a rotating body with respect to its rotation. The moment of inertia plays much the same role in rotational dynamics as mass does in linear dynamics, describing the relationship between angular momentum and angular velocity, torque and angular acceleration, and several other quantities. The symbols I and J are usually used to refer to the moment of inertia or polar moment of inertia.
While a simple scalar treatment of the moment of inertia suffices for many situations, a more advanced tensor treatment allows the analysis of such complicated systems as spinning tops and gyroscopic motion.
The concept was introduced by Leonhard Euler in his 1765 book Theoria motus corporum solidorum seu rigidorum; he discussed the moment of inertia and many related concepts, such as the principal axis of inertia.
Read more about this topic: Statics
Other articles related to "moment of inertia, inertia":
... In order to compare formulations of the inertia matrix in terms of a product of skew-symmetric matrices and in terms of a tensor formulation, the following identities are ... matrix associated with the position vector R=(x, y, z), then the product in the inertia matrix becomes This product can be computed using the matrix formed by the outer product using the ...
... The moment of inertia of an object, symbolized by I, is a measure of the object's resistance to changes to its rotation ... The moment of inertia is measured in kilogram metre² (kg m²) ... increasing the mass of an object increases the moment of inertia ...
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