Question

Unit for moment of inertia is _____________

(a) m^3

(b) m^4

(c) m^2/sec

(d) m^3/sec

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Asked question is from Moments of Inertia of Areas topic in portion Centres of Gravity, Moments of Inertia, Orthographic Reading and Conversion of Views of Engineering Drawing

Answer 1

Right answer is (b) m^4

Explanation: The moment of inertia is sum of products of areas and squares of perpendicular distances from center of gravity. Since here we are considering the planar objects the area will have unit of m2 and square of distance gives another m^2 product is m^4.