Is the Cloud of Hydrogen Gas Likely to Collapse?

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Homework Statement


A cloud consists of 8 solar masses of hydrogen gas (H2). Its temperature is 20 K and its radius is 0.6 light years. Will it collapse?


Homework Equations


jeans mass


3. The Attempt at a Solution [/b
I've tried to use jeans mass to solve this however I am finding the formula difficult to understand
 
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Show your work.
 
So far I'm using the formula
3/2kT <GMm/R
And (3KT/2Gm) x k >mj

I'm substituting m=2.167x10^-27
G=6.67x10^-11
K=1.38x10^-23
T=20
R=0.6

However I'm not sure what it is exactly that I'm gaining from using these formulae?
I'm getting that (3kT/2Gm) x R = 1.115011357 x 10^15 ?
I'm aiming to get an answer of
Jeans mass = 1.05 x 10^31 kg
Which is less than 8 solar masses (1.6 x 10 ^31) so it will collapse?
 
I struggled to follow your logic above. Seem to be a few typos:
(3KT/2Gm) x k >mj
(3kT/2Gm) x R = Mj ?
(3kT/2Gm) x R = 1.115011357 x 10^15
√((3kT/2Gm) x R) = 1.115011357 x 10^15 ?
Also, I don't see online a formula with that 3/2 factor. I see one with 15/4pi, another that approximates that to 1. Anyway, using your 3/2 I get that the Jeans length/radius = 0.84, which suggests to me it won't collapse. (I'm a bit confused over whether the Jeans length is a radius or a diameter, but if it's a diameter then the actual radius is much too large to collapse.)
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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