Question

What is centroid, centre of gravity and moment of inertia

Answer 1

Answer:

Centre of Gravity (C.G.) is that point through which the resultant of a system of parallel forces formed by the weights of all particles of the body passes. The centre of area of such figure is known as centroid. It is also called the geometrical centre or the centre of gravity.

Answer 2

Rotational inertia is important in almost all physics problems that involve mass in rotational motion. It is used to calculate angular momentum and allows us to explain (via conservation of angular momentum) how rotational motion changes when the distribution of mass changes.