A person with mass mp = 72 kg stands on a spinning platform disk with a radius of R = 1.71 m and mass md = 195 kg. The disk is initially spinning at ω = 1.9 rad/s. The person then walks 2/3 of the way toward the center of the disk (ending 0.57 m from the center).

If the person now walks back to the rim of the disk, what is the final angular speed of the disk?

final angular velocity of disk: 3.0526
change in total KE: 540.25
Centripetal acceleration of the person when she is at R/3: 5.3024

Question

A person with mass mp = 72 kg stands on a spinning platform disk with a radius of R = 1.71 m and mass md = 195 kg. The disk is initially spinning at ω = 1.9 rad/s. The person then walks 2/3 of the way toward the center of the disk (ending 0.57 m from the center). 

If the person now walks back to the rim of the disk, what is the final angular speed of the disk? 

final angular velocity of disk: 3.0526 
change in total KE: 540.25 
Centripetal acceleration of the person when she is at R/3: 5.3024

anonymous · Answer

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anonymous · Answer

the picture is the most important part of any physics problem ^_^