New Angular Velocity of Star with Diameter Shrink to 0.17 Times

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The discussion revolves around calculating the new angular velocity of a star with a mass of 1.1e31 kg after its diameter shrinks to 0.17 times its original size. Participants emphasize the importance of identifying conserved quantities in the process, suggesting that conservation laws such as angular momentum should be applied. One user advises against simply providing a solution, highlighting the forum's rules against doing homework for others. The conversation encourages understanding the principles behind the problem rather than just seeking answers. Ultimately, the focus is on applying conservation equations to derive the new angular velocity.
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The mass of a star is 1.1e31 kg and its angular velocity is 1.40×10-7 rad/s. Find its new angular velocity if the diameter suddenly shrinks to 0.17 times its present size. Assume a uniform mass distribution before and after. [Icm for a solid sphere of uniform density is 2/5 mr^2].


Can anyone helps me please?... i don't know hoyw to begin this exercise...
 
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Hi Naldo6,

Naldo6 said:
The mass of a star is 1.1e31 kg and its angular velocity is 1.40×10-7 rad/s. Find its new angular velocity if the diameter suddenly shrinks to 0.17 times its present size. Assume a uniform mass distribution before and after. [Icm for a solid sphere of uniform density is 2/5 mr^2].


Can anyone helps me please?... i don't know hoyw to begin this exercise...

What quantity would be conserved in this process?
 
can u solve me this problem?...
 
Naldo6 said:
can u solve me this problem?...

I'm sorry Naldo, but forum rules here prohibit doing someone else's homework for them. If I were to just solve the problem for you the multitude of homework helpers and mentors would unite and rise against me and crush me like a worm.

So instead of that, think of what quantity would be conserved here. There should only be a few conserved quantities that you have studied: energy, momentum, etc. What other conservation equation have you studied, that applies here? Once you have determined that, you can use that to write an equation that will help you solve the problem.
 

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