Calculating Rotation Period of a Collapsing Interstellar Cloud

AI Thread Summary
The discussion revolves around calculating the rotation period of a collapsing interstellar cloud transitioning into a star. The initial parameters include a mass of 2.03×10^30 kg and a radius of 1.03×10^13 m, with a rotation period of 1.43×10^6 years. The calculations involve determining angular velocity and using the moment of inertia to find the new rotation period after collapse, resulting in a value of approximately 2.42 days. A participant expresses confusion over an expected answer of 88.9 minutes, prompting a suggestion to verify the provided answer with the teacher. The conversation highlights the complexities of astrophysical calculations and the importance of accuracy in homework solutions.
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Homework Statement


A uniform, spherical cloud of interstellar gas has mass 2.03×1030 kg and radius 1.03x1013m and is rotating with period 1.43×106 years. The cloud collapses to from a star 7.03x108m in radius. Find the star's rotation period.

Homework Equations


I1ω1=I2ω2
Θ=ωt

The Attempt at a Solution


Determine ω:[/B]
2π=ω(1.43×106)
ω=4.4×10-6
Use Moment of Inertia Equation: I=2/5(mr2)
I1=8.61×1055
I2=4.01×1047
∴ ω2=944.74 rad/year
Determine t:
Θ=ωt
∴ t=Θ/ω
=2π/944.74
=6.7×10-3
=2.42 days

Hey guys, I've been trying to do this homework question for a while now but I can't seem to get to the answer of 88.9 minutes. Any help getting there is much appreciated. Thank you all in advance.
 
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I agree with your method and answer.
 
Wow odd. I will ask the teacher about the provided answer being incorrect then, thank you for shedding some light on this haruspex.
 
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