Question

Calculate the moment of inertia of the rod about its center having a mass of 11 kg and length of 29 cm.

(a) .091 kgm^2

(b) .072 kgm^2

(c) .076 kgm^2

(d) .077 kgm^2

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Answer 1

The correct choice is (d) .077 kgm^2

The explanation: The moment of inertia of the rod about its center can be calculated using the formula I=ML^2÷12. The mass of the rod about its center and length is given. I=(11)×.0833×(.29)^2=.077 kgm^2. It depends upon the orientation of the rotational axis.