Question

What is parallel axis theorem and to whom it is applied?

(a) Theorem used to add the two mutually perpendicular moment of inertias for areas

(b) Theorem used to add the two mutually perpendicular moment of inertias for volumes

(c) Theorem used to add the two mutually perpendicular moment of inertias for linear distances

(d) Theorem used to add the two mutually perpendicular moment of inertias for vectors

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This question is from Moment of Inertia for Areas topic in section Moments of Inertia of Engineering Mechanics

Answer 1

Right option is (a) Theorem used to add the two mutually perpendicular moment of inertias for areas

Best explanation: Parallel axis for any area is used to add the two mutually perpendicular moment of inertias for areas. It gives a moment of inertia perpendicular to the surface of the body. That is the moment of inertia perpendicular to the surface in considerance.