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Cosmology question [OCR A Physics] Chandrasekhar..

hey, ive started revision for the cosmology paper which will be this tuesday, however im having a few problems with the chandrasekhar limit.

Whats the difference between the chandrasekhar limit (1.4M) and the limit which i see all the time in the exam papers (3M) about when stars die or something?

I dont know if anyone knows what im on about, but if youve done a few papers youll know. Please point me in the right direction =]

Thanks in advance, keef.
Reply 1
Fate of star

If the core of the star is > 1.4 times( Chandrasekhar Limit) the mass of the sun --> Neutron Star

If the core of the star is > 3 times the mass of the sun --> Black hole

Note a star with a core @ 3 times the mass of the Sun, Since there are no known mechanisms left to stop the core collapsing to an infinite dense point called a singularity.
Reply 2
oooh thanks ebam_uk =] that really clears things up. Just did a question and realised i didnt check my post earlier on during the day.. got the question completely wrong :colondollar:.

Thanks a lot, much appreciated *Rep* =D
Reply 3
I dunno If I'm right on this, (Its probably best someone confirms before youu believe me), but I though that if the mass of the star after the hellium flash was greater than the chandrasekhar limit, then the star would end up as a neutron star (or a blackhole if this mass is greater than 3 times the mass of the sun) and a white dwarf if this mass is less.
Reply 4
eponymous
I dunno If I'm right on this, (Its probably best someone confirms before youu believe me), but I though that if the mass of the star after the hellium flash was greater than the chandrasekhar limit, then the star would end up as a neutron star (or a blackhole if this mass is greater than 3 times the mass of the sun) and a white dwarf if this mass is less.



ebam_uk
Fate of star

If the core of the star is > 1.4 times( Chandrasekhar Limit) the mass of the sun --> Neutron Star

If the core of the star is > 3 times the mass of the sun --> Black hole

Note a star with a core @ 3 times the mass of the Sun, Since there are no known mechanisms left to stop the core collapsing to an infinite dense point called a singularity.


You are correct, after the "helium" flash, I think basically you have the core left, so if this is greater the 1.4 you get a neutron star and if it is greater the 3 times the mass of the sun you get a black hole.

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