JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2018
- Hard
- MCQ
A thin circular disc is in the \(xy\) plane as shown in the figure. The ratio of its moment of inertia about \(z\) and \(z'\) axes will be

Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(1:3\)
Step-by-step Solution
Detailed explanation
As we know, moment of inertia of a disc about an axis passing through \(C.G.\) and perpendicular to its plane, \({I_z}\, = \frac{{m{R^2}}}{2}\) Moment of inertia of a disc about a tangential axis perpendicular to its own plane,
\({I_z}'\, = \frac{3}{{20}}m{R^2}\)
\({I_z}/{I_z}'\, = \frac{{m{R^2}}}{2}/\frac{{3m{R^2}}}{2}\, = 1/3\) 
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