A uniform disk turns at 3.7 rev/s around a frictionless spindle. Anonrotating ro

Question

A uniform disk turns at 3.7 rev/s around a frictionless spindle. Anonrotating rod, of the same mass as the disk and length equal tothe disk's diameter, is dropped onto the freely spinning disk. Theythen turn together around the spindle with their centerssuperposed. What is the angular frequency in rev/s of thecombination?

Explanation / Answer

Conservation of angular momentum => I* = I'*' (I, I' are the moment of inertia of the disk and the systemdisk+rod) Let M and R be the mass and the radius of the disk => I = (1/2)M*R^2 and : I' = I+ I(rod) = (1/2)M*R^2 + (1/12)M*(2R)^2 =(5/6)M*R^2 => '= *I/I' = (3/5)*3.7 = 2.22 rev/s

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.