What do I use to determine rotational speed of solar nebula?

[shejinx]

Hi there.

I need some help with this I have confused myself ... I am trying to determin the rotational spped of our solar nebula as it would have been at r=40 000 AU. I have the facts that at 40 AU v=5km/second. what I am not sure on is do I use L=m*v*r? if so do I use the mass of the sun as the mass for the solar nebula? or is there another way using p^2=A^3?
Like I said I am very confused on this matter.

Thanks for all and any help

 

[Kurdt]

If you're using conservation of angular momentum then you will need to assume the sun has the same angular momentum as the original nebula did. You can also assume the mass of the nebula is the same as that of the sun. Depends what you want to do really. The sun has of course lost a lot of angular momentum through stellar winds.