For a uniform cylinder of length L and radius R the moment of inertia is I₁. Now for similar situation but length L/2 and radius R/2 moment of inertia is I₂.
Find I₁ / I₂.
Correct Answer :
32
Solution :
The correct answer is 32.
Step-by-step Explanation:
Let us consider a uniform solid cylinder of mass , length , and radius .
As observed in the provided image, the axis of rotation for both cylinders is perpendicular to their length and passes through their respective centers of mass.
The moment of inertia of a uniform solid cylinder about an axis perpendicular to its length and passing through its center is given by the formula:
Since both cylinders are made of the same uniform material, they have the same mass density .
The mass of a cylinder is equal to its density multiplied by its volume:
1. For the first cylinder:
Length = , Radius =
The mass is:
The moment of inertia is:
2. For the second cylinder:
Length = , Radius =
The mass is:
The moment of inertia is:
Substitute into the equation:
Factor out from the terms inside the brackets:
3. Finding the ratio:
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