Seven identical circular planar disks, each of mass $M$ and radius $R$ are welded symmetrically as shown.
The moment of inertia of the arrangement about the axis normal to the plane and passing through the point $P$ is -
- $\frac{19}{2} MR^2 $
- $\frac{55}{2} MR^2 $
- $\frac{73}{2} MR^2 $
- $\frac{181}{2} MR^2 $
The Correct Option is D
Solution and Explanation
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Concepts Used:
System of Particles and Rotational Motion
- The system of particles refers to the extended body which is considered a rigid body most of the time for simple or easy understanding. A rigid body is a body with a perfectly definite and unchangeable shape.
- The distance between the pair of particles in such a body does not replace or alter. Rotational motion can be described as the motion of a rigid body originates in such a manner that all of its particles move in a circle about an axis with a common angular velocity.
- The few common examples of rotational motion are the motion of the blade of a windmill and periodic motion.