Enter the moment of inertia about the axis and the total mass into the calculator to determine the radius of gyration.

Radius of Gyration Formula

The following equation can be used to calculate the radius of gyration.

kx = Sqrt ( Ix / m ) 
  • Where kx is the radius of gyration
  • Ix is the moment of inertia of the point mass
  • m is the total mass

To calculate the radius of gyration, take the square root of the result of the momentum of inertia divided by the total mass.

Radius of Gyration Definition

A radius of gyration is the distance to a point that would have a moment of inertia as a distributed mass.

Radius of Gyration Example

How to calculate radius of gyration?

  1. First, determine the moment of inertia.

    Calculate the moment of inertia of the point mass. If you are unsure of how to calculate this value, you can visit the calculator linked above.

  2. Next, determine the total mass.

    Calculate or measure the total mass of the point.

  3. Finally, calculate the radius of gyration.

    Using the formula presented above, calculate the radius of gyration.

FAQ

What is a radius of gyration?

A radius of gyration is the distance to a point that would have the same moment of inertia as a body distributed mass if all of the mass was located at the one point.