Parallel axis theorem: These theorems help students calculate the

These theorems help students calculate the moment of inertia of various bodies about different axes with ease. They are especially useful when direct computation is complex or not practical. Understanding these theorems allows you to solve many numerical and conceptual problems in rotational dynamics confidently. The parallel axis theorem is the method to find the moment of inertia of the object about any axis parallel to the axis passing through the centroid. This This article explores the theorem ’s theory, its application in structural engineering, and a worked example involving a steel truss. Learn how to calculate the moment of inertia of a rigid body about any parallel axis using the parallel axis theorem . See the formula, derivation, and examples for different shapes such as rod, ring, disc, and sphere.