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A vinyl record that is 12 inches in diameter spins at a constant frequency of 33...

A vinyl record that is 12 inches in diameter spins at a constant frequency of 33 1/3 rpm. It can be modeled as a solid disk with mass 225g. For the purpose of this problem we will assume there's no torque on the record; no friction to slow it down or motor to speed it up.

1) What is the angular momentum of the record? What is its kinetic energy?

You place a nickel weighing 5.0 g on the very outer edge of the record ( you can assume all its mass is at one point). The penny has no angular momentum of its own prior to being placed on the record.

2) What is the new angular velocity of the record? By what fraction has the record's kinetic energy decreased?

If you wanna handwrite, please make it clear. Thanks a lot!
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