The moment of inertial of a thin rod is:
Correct answer: D. 1/12 mL2
- A. 1/2 mL2
- B. 1/4 m3L
- C. 1/12 mL
- D. 1/12 mL2
Explanation
The moment of inertia of an object is a measure of its resistance to changes in its rotation. For a thin rod of length L and mass m, rotating about an axis through its center and perpendicular to its length, the moment of inertia is given by the formula I = (1/12) mL2. This correctly accounts for both the mass and the distribution of that mass along the length of the rod. Option A represents the moment of inertia of a different geometric shape, option B has incorrect units and a non-standard form, and option C lacks the correct dimensions for a moment of inertia. Thus, Option D is the correct and only valid choice.
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