Physics
Mechanics
Easy
Question
A solid aluminium sphere of radius R has moment of inertia I about an axis through its centre. The moment of inertia about a central axis of a solid aluminium sphere of radius 2R is
- 4I
- 8I
- 16I
- 32I
The correct answer is: 32I
The sphere of twice the radius has eight times the volume and eight times the mass, and the r2 term in 
also becomes four times larger.
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