radius of gyration

American  

noun

Physics.

1. the distance from an axis at which the mass of a body may be assumed to be concentrated and at which the moment of inertia will be equal to the moment of inertia of the actual mass about the axis, equal to the square root of the quotient of the moment of inertia and the mass.

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radius of gyration British  

noun

1. a length that represents the distance in a rotating system between the point about which it is rotating and the point to or from which a transfer of energy has the maximum effect. Symbol: k or r . In a system with a moment of inertia I and mass m , k ² = I / m

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Etymology

Origin of radius of gyration

First recorded in 1875–80

Example Sentences

Radius of gyration, coefficient of restitution and other obscure forces cause tethered pins to fly around differently than their free-fall counterparts.

From Los Angeles Times

The attenuated polarization potential in LGS-mPol yields a spectrum that is red-shifted from experiment by 0.7 eV, which makes sense given the larger radius of gyration predicted by this model.

From Science Magazine

In mechanics, the ellipsoid of gyration or inertia is such that the perpendicular from the centre to a tangent plane is equal to the radius of gyration of the given body about the perpendicular as axis; the “momental ellipsoid,” also termed the “inverse ellipsoid of inertia” or Poinsot’s ellipsoid, has the perpendicular inversely proportional to the radius of gyration; the “equimomental ellipsoid” is such that its moments of inertia about all axes are the same as those of a given body.

From Project Gutenberg

Although a column is normally subjected to compressive stresses, when the slenderness ratio—that is, the length divided by the radius of gyration of the cross section—becomes great, a secondary bending stress may be produced.

From Project Gutenberg

If k be the radius of gyration of a bob round a horizontal axis through its centre of gravity, h the distance of its centre of gravity below its point of suspension, and k’ the radius of gyration of the bob round the centre of suspension, then k′� = h� + k�.

From Project Gutenberg