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title: "Two identical solid disks, each of mass \\( M \\) and radius \\( R \\), are welded together so that they touch at exactly one point on their rims. Determine the moment of inertia of the combined object about an axis that is perpendicular to the plane of the disks and passes through their point of contact. Hint: The moment of inertia of a solid disk about its center is \\(\\frac{1}{2} M R^{2}\\)."
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url: "https://nerd-notes.com/ubq/104421/"
date_modified: "2025-11-02T13:35:21+00:00"
---

# Two identical solid disks, each of mass \( M \) and radius \( R \), are welded together so that they touch at exactly one point on their rims. Determine the moment of inertia of the combined object about an axis that is perpendicular to the plane of the disks and passes through their point of contact. Hint: The moment of inertia of a solid disk about its center is \(\frac{1}{2} M R^{2}\).

Two identical solid disks, each of mass \( M \) and radius \( R \), are welded together so that they touch at exactly one point on their rims. Determine the moment of inertia of the combined object about an axis that is perpendicular to the plane of the disks and passes through their point of contact. Hint: The moment of inertia of a solid disk about its center is \(\frac{1}{2} M R^{2}\).

- **A.** \[ M R^{2} \]
- **B.** \[ 3 M R^{2} \]
- **C.** \[ 2 M R^{2} \]
- **D.** \[ \dfrac{3}{2} M R^{2} \]
- **E.** \[ 4 M R^{2} \]

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/104421/*