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jdw_
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Hi, I am wondering if somebody could explain how to answer these questions, it is from "Foundations of astrophysics" ch.15 q15.10
Suppose the mass density of a star as a function of radius is
p(r)=p0[1-(r/R)^2]
where R is the radius of the star
a) Find the mass M of the star in terms of p0 and R
b) Find the mean density of the star in terms of p0
c) Show that the central pressure of the star is:
Pc=15/16pi x GM^2/R^4
I have a good idea on how to do b) and c) but i need help with a)
useful equations :
P(r)= -GM(r)p(r)/r^2
M(r) = 4pi r^2 p(r)
Suppose the mass density of a star as a function of radius is
p(r)=p0[1-(r/R)^2]
where R is the radius of the star
a) Find the mass M of the star in terms of p0 and R
b) Find the mean density of the star in terms of p0
c) Show that the central pressure of the star is:
Pc=15/16pi x GM^2/R^4
I have a good idea on how to do b) and c) but i need help with a)
useful equations :
P(r)= -GM(r)p(r)/r^2
M(r) = 4pi r^2 p(r)