Calculating New Period of a Collapsed Sun Using Conservation of Angular Momentum

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The discussion revolves around calculating the new period of a sun that collapses into a dwarf star using conservation of angular momentum. The initial parameters include a radius of 8.1 x 10^8 m and a period of 38 days. Participants confirm that the angular velocity is calculated as 2π/38 days and affirm the relevance of conservation of angular momentum to the problem. Ultimately, the user expresses gratitude after understanding how to solve the problem. The conversation highlights the importance of angular momentum in astrophysical transformations.
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Suppose a sun has a radius of 8.1 x10^8 m and a period of 38 days. If is collapses to a dwarf of radius 8.3 x 10^6 m, what is the new period (in days)? I= 2/5mr^2
I totally don't know how to do the problem. :frown:
Is it related to conservation of angular momentum?
Does the angular velocity equal to 2pi/38 days?
thx!
 
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Yes - to both questions! :)
 
Tide said:
Yes - to both questions! :)
thx, I get the answer now :)
 

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