Question

There is perpendicular axis theorem for the calculation of the radius of gyration.

(a) True

(b) False

This question was addressed to me during an interview.

My doubt stems from Radius of Gyration of an Area topic in chapter Moments of Inertia of Engineering Mechanics

Answer 1

The correct choice is (b) False

The explanation is: There is no perpendicular axis theorem for the radius of gyration. In spite, there is the theorem as parallel axis for any area. Thus we have the theorem which is used to add the two mutually perpendicular moment of inertias.