Question

Calculate the moment of inertia of the flywheel of mass 45 kg and radius of 2 m.

(a) 185 kg-m^2

(b) 180 kg-m^2

(c) 175 kg-m^2

(d) 170 kg-m^2

This question was posed to me in an interview.

My question comes from Motors Rating and Heating in chapter Rating and Heating of Motors of Electric Drives

Answer 1

Correct choice is (b) 180 kg-m^2

Easiest explanation: The moment of inertia of the flywheel can be calculated using the formula I=M(R^2). The mass of flywheel and radius is given. I=(45)×(2)^2=180 kg-m^2. It depends upon the orientation of the rotational axis.