Moment of Inertia Calculator > Instructions

Instructions for using Moment of Inertia Calculator

This moment of inertia calculator is developed to help calculation of area, centroid, moment of inertia, section modulus and radius of gyration for Rectangular, Circular, Angle, T , Channel and I sections of structural members.

(i) This calculator takes the origin "O" of reference axes at the intersection of the horizontal axis (o-p) coinciding with the lower-most edge of the section and vertical axis (o-q) coinciding with the extreme left edge of the section. All the distances should be entered in "cm" and you will get  the calculated values in terms of corresponding units of "cm". If the distances are entered in "inch" the values would be in the corresponding units in "inch".

(ii) The position of centroid 'C" is calculated in terms of its coordinates with references to origin of axes "O".

(iii) The moment of inertia is calculated about the x-x axis and y-y axis passing through the centroid of the section.

(iv) In case of hollow rectangular or hollow circular sections, the section should be symmetric about both x-x and y-y axes i.e. with uniform thickness.

(v) In case of I section and T section, the section should be symmetric about y-y axis.

Rectangular

Hollow Rectangular

Hollow Circular