Question:
Figure shows triangular lamina which can rotate about different axis of rotation. Moment of inertia is maximum about the axis
Figure shows triangular lamina which can rotate about different axis of rotation. Moment of inertia is maximum about the axis
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Moment of inertia is maximum about the axis from which the mass distribution is farthest.
Updated On: Feb 4, 2026
- QS
- QR
- PQ
- PR
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The Correct Option is B
Solution and Explanation
Step 1: Recall the concept of moment of inertia.
Moment of inertia depends on how far the mass of the body is distributed from the axis of rotation. Greater the average distance of mass elements from the axis, greater is the moment of inertia.
Step 2: Analyze given axes.
Among the given axes, axis QR lies along the base of the triangular lamina, such that most of the mass of the lamina is distributed at larger perpendicular distances from this axis.
Step 3: Compare with other axes.
Axes PQ, PR, and QS pass closer to the bulk of the mass, resulting in smaller average distances of mass elements from these axes.
Step 4: Final conclusion.
Hence, the moment of inertia is maximum about axis QR.
Moment of inertia depends on how far the mass of the body is distributed from the axis of rotation. Greater the average distance of mass elements from the axis, greater is the moment of inertia.
Step 2: Analyze given axes.
Among the given axes, axis QR lies along the base of the triangular lamina, such that most of the mass of the lamina is distributed at larger perpendicular distances from this axis.
Step 3: Compare with other axes.
Axes PQ, PR, and QS pass closer to the bulk of the mass, resulting in smaller average distances of mass elements from these axes.
Step 4: Final conclusion.
Hence, the moment of inertia is maximum about axis QR.
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