Radius of Gyration of rectangular solid section is the square root of the moment of inertia of a solid rectangular section to the cross sectional area of that solid rectangular body.
Radius of Gyration of Rectangle Formula
Mathematically, radius of gyration of rectangular section can be expressed as;
[latex]K=sqrt{frac{I}{A}}=sqrt{frac{db^{3}/12}{bd}}[/latex]
..
[latex]K=frac{b}{sqrt{12}}[/latex]
