A student sits at rest on a piano stool that can rotate without friction. The moment of inertia of the student-stool system is 4.2 . A second student tosses a 1.1 mass with a speed of 3.0 to the student on the stool, who catches it at a distance of 0.45 from the axis of rotation. What is the final rotational speed of the stool, student and mass?

Question

A student sits at rest on a piano stool that can rotate without friction. The moment of inertia of the student-stool system is 4.2 . A second student tosses a 1.1  mass with a speed of 3.0  to the student on the stool, who catches it at a distance of 0.45 from the axis of rotation. What is the final rotational speed of the stool, student and mass?

Anonymous · Answer

the I for the added mass is mr^2. The w for the added mass is v/r so do this, add the two momentums and set them equal to (Itotal)Wfinal and solve for wfinal