A turntable has a moment of inertia of 3.00 *10^-² kg·m² and spins freely on a frictionless bearing at 25.0 rev/min. A 0.600-kg ball of putty is dropped vertically onto the turntable and sticks at a point 0.100 m from the center. What is the new rate of rotation of the system?

Question

Quizplus · Accepted Answer

The conservation of angular momentum applies here. The initial angular momentum is equal to the final angular momentum. Calculate the initial angular momentum using the moment of inertia and initial angular velocity. Then, calculate the final moment of inertia by adding the moment of inertia of the putty (treated as a point mass) to the turntable's moment of inertia. Solve for the final angular velocity and convert it to rev/min.

A Turntable Has a Moment of Inertia of 3