4. A pottery wheel of radius 20cm and mass M is freely rotating about an axis through its center at 87 rads/s. A blob of very dense clay of mass 5kg is gently placed on the spinning wheel halfway up its radius (i.e. 10cm from the axis of rotation). This causes the rate of rotation of the pottery wheel to drop to 7.8a rads/s. You can treat the pottery wheel as a uniform disk and the blob of clay as a point particle. The moment of inertia of a disk about an axis through its center is given by I = MR. (a) Write down expressions for the angular momentum of the system before and after the blob has been placed on the wheel. (b) Hence, find the mass M of the pottery wheel.

4. A pottery wheel of radius 20cm and mass M is freely rotating about an axis through its center at 87 rads/s. A blob of very dense clay of mass 5kg is gently placed on the spinning wheel halfway up its radius (i.e. 10cm from the axis of rotation). This causes the rate of rotation of the pottery wheel to drop to 7.8a rads/s. You can treat the pottery wheel as a uniform disk and the blob of clay as a point particle. The moment of inertia of a disk about an axis through its center is given by I = MR. (a) Write down expressions for the angular momentum of the system before and after the blob has been placed on the wheel. (b) Hence, find the mass M of the pottery wheel.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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