Question
A uniform circular platform of mass 100 kg and radius 3.0 m is mounted on a...
A uniform circular platform of mass 100 kg and radius 3.0 m is mounted on a frictionless vertical axle and is initially stationary. A girl of mass 40 kg stands on the rim of the platform. She begins to walk along the rim at a speed of 1.5 m/s relative to the ground in clockwise direction. What is the resulting angular velocity of the platform.
Homework Answers
Answer #1
It can be solved using conservation of angular momentum.
About the center of disc, angular momentum of girl is
In cylindrical polar coordinated.
therefore
The angular momentum of platform is
as initial angular momentum was 0
final must be 0.
so
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