Integrating dP/dr over the Sun

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SUMMARY

The discussion focuses on integrating the hydrostatic equilibrium equation, specifically dP/dr = -Gmp/r^2, to estimate the central pressure of the Sun, modeled as a uniform sphere of hydrogen gas with an average density of 1440 kg/m³. The integration process involves substituting mass m with 4/3πr³ρ, leading to the equation dP/dr = -4πGρr²/3. Upon integrating from the Sun's radius to the core, the estimated central pressure is calculated to be approximately 1.4 million atmospheres, which is significantly lower than the actual central pressure of about 250 billion atmospheres.

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Homework Statement



Consider the Sun to be a sphere of hydrogen gas of uniform density equal to its
average density (1440 kg/m3).
a) Integrate the equation of hydrostatic equilibrium for dP/dr from the Sun’s radius to the
core to estimate the central pressure in Pa and in atmospheres. Assume the pressure at the
surface is zero. [Note: your estimate will fall far short of the true value that can be
derived using a more realistic density profile, about 250 billion atmospheres, but that’s ok
for our purposes]

Homework Equations



dP/dr = -Gmp/r^2 (p = density)


The Attempt at a Solution



I replaced m with 4/3pir^3p which yields
dP/dr = -4piGrp^2/3
and integrated from R to 0 yielding 2piGp^2R^2/3
and filling in the values and Radius of the sun, I get 1.4e6 atm of pressure.
Does this make sense? (Is it consistent with what the question is asking)
 
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