The moment of inertia of a solid sphere of radius R about its diameter is the same as that of a disc of radius 2R about its diameter. The ratio of their masses is:
Correct answer: A. 5 : 2
- A. 5 : 2
- B. 5 : 8
- C. 4 : 1
- D. 2 : 1
Explanation
This is the following solution: Moment of inertia of a solid sphere=2/5mr², Moment of inertia of disk=1/2mr² By taking their ratio answer would be 5:2.
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