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helokit
What is the angular momentum of a figure skater spinning (with arms in close to her body) at 5.0 rev/s, assuming her to be a uniform cylinder with a height of 1.5 m, a radius of 17 cm, and a mass of 55 kg.

(cool.gif How much torque is required to slow her to a stop in 5.0 s, assuming she does not move her arms?
mN


For the first one i put I=lw
I=i/2MR^2=.798
.798*W=.798*31.4(i converted srev/s to rad/s)

27.5 kgm2/s is that right for the momentum?


how do i do b.
iTakePhysics22
you can get the torque by using the formula:

T=L/t

where T is torque, L is angular momentum and t is seconds to stop.
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