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Glite Dictionary
moment of inertia

moment of inertia

1 7.8
A number showing how hard it is to change an object's spin based on how its mass is spread
  • noun
  • /ˈmoʊmənt əv ɪˈnɜrʃə/
  • Specialized
translation icon : momento de inercia
  • Only redistribution of the earth's mass can change its moment of inertia.
  • polar moment of inertia
  • mass moment of inertia
  • constant moment of inertia

So I'll write SDM and this is what we call the moment of inertia of a continuous body.

Examples

  • The bat speed will, in turn, depend on the bat weight, or more precisely, its moment of inertia.

    Academic text (2010)

  • Rigid bodies have constant moments of inertia.

    Academic text (1995)

  • This will increase my moment of inertia, so I will spin... faster.

    Ice Princess (2005)

  • It's got one small moment of inertia about the long axis.

  • The mass stays the same, but the moment of inertia gets smaller.

  • Let us think about the moment of inertia of a coin or a disk.

  • The unique rotor design provides a very low moment of inertia for strong acceleration and dynamic behavior.

    Academic text (2005)

  • We must distinguish between angular momentum and moment of inertia.

    Blog text (28)

  • As with centroids, moments of inertia of common shapes can be looked up in tables.

    Blog text (26)

  • The moment of inertia of a spinning disk depends on how its mass is distributed around the center.

Surface Forms

moment of inertia singular
moments of inertia plural

Morphology

moment + of + inertia

The compound clearly combines 'moment' (a rotational effect) and 'inertia' (resistance to change in motion), so a learner who knows the constituents will likely infer it relates to rotational resistance; however, the precise quantitative meaning (dependence on mass distribution and angular acceleration) is technical and requires domain knowledge. Because the core idea is partly recoverable from the parts but the full interpretation is specialized, it is best classified as semi-transparent.

Etymology

Moment of inertia comes from two simple ideas: moment (a push that makes something turn around a point) and inertia (how much an object resists changes in motion). That's why it is a picture of how hard it is to start or stop something spinning, or in other words 'resistance to change in rotation'.