A ballerian spins initially at 1.5rev/s when arms are extended. She then draws in her arms to her body and her moment of intertia is .88kg m^2 and her angular speed increases to 4.0rev/s. Determine the network she did to increase her angular speed?(adsbygoogle = window.adsbygoogle || []).push({});

So i first needed to solve for the initial momentum , which i did using equation IW=I2W2, and i got .43kg m 2, then to get the network i used w=(final)IW^2 - (initial) IW^2

i got 518J, i am not to sure if i did this right. Can anyone please tell me if my math is correct ? Also for angular speed, in the work calculation i would need to get that to rad/s if im correct so multiply by 2pi ?

Thanks Guys

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# Homework Help: Net Work Problem, Rotational Motion, need help

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