Question

Calculate the mass of the solid cylinder having a mass of 4 kgm^2 and radius of 4 m & length of 12 m.

(a) 64 kgm^2

(b) 68 kgm^2

(c) 67 kgm^2

(d) 69 kgm^2

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My question is from Motors Rating and Heating in section Rating and Heating of Motors of Electric Drives

Answer 1

Right choice is (a) 64 kgm^2

The explanation is: The moment of inertia of the solid cylinder can be calculated using the formula I= M(l^2÷12+R2^2÷4). The mass of solid cylinder and radius, the length is given. I=(4){(16)}= 64 kgm^2. It depends upon the orientation of the rotational axis.