JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2024
- Hard
- Numerical
Three balls of masses \(2 \mathrm{~kg}, 4 \mathrm{~kg}\) and \(6 \mathrm{~kg}\) respectively are arranged at centre of the edges of an equilateral triangle of side \(2 \mathrm{~m}\). The moment of inertia of the system about an axis through the centroid and perpendicular to the plane of triangle, will be _______\(\mathrm{kg} \mathrm{m}{ }^2\).
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(4\)
Step-by-step Solution
Detailed explanation
Moment of inertia about \(\mathrm{C}\) and perpendicular to the plane is:
\(\mathrm{I} =\mathrm{r}^2[2+4+6]\)
\(=\frac{1}{3} \times 12\)
\(\mathrm{I} =4 \mathrm{~kg}-\mathrm{m}^2\)
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