Finding Earth's Mass Using Gauss Law

AI Thread Summary
The discussion focuses on calculating Earth's mass using its volume mass density and Gauss's Law for gravitation. The density function is given as ρ = A - Br/R, with specific values for A, B, and Earth's radius R. Participants express confusion about the application of Gauss's Law and the units involved in the equations presented. The gravitational flux through a closed surface is proportional to the total mass within that surface, as stated by Gauss's Law. The conversation emphasizes the need for clarity in the equations and their physical interpretation.
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Is it possible to find the mass of the Earth based on the Earth's volume mass density, roe = A-Br=R, where A = 1.42 x 104 kg/m3, B = 1.16 x 104 kg/m3, and Earth’s radius
R = 6.370 x 106 m

I know that based on Gauss Law that (closed integral) g x da = -4Gmin, where g is the total electric field due to the inside and outside of the closed surface. I don't see how this is possible.
 
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Your equation and the units don't make sense.
 
This was the entire question
Consider a closed surface S in a region of gravitational field g. Gauss’s law for gravitation tells us that the gravitational flux through surface S is linearly proportional to the total mass min occupying the volume contained by S. More specifically, Gauss’s law states that
(closed integral)g x da = -4Gmin :
Note that g here is the total electric field, due to mass sources both inside and outside S. The value of G, the gravitational constant, is about 6.673 x10-11 N m2/kg2.
(a) Earth’s volume mass density, at any distance r from its center, is given approximately by the function p = A-Br/R, where A = 1.42 x 104 kg/m3, B = 1.16 x 104 kg/m3, and Earth’s radius R = 6.370 x 106 m. Calculate the numerical value of Earth’s mass M. Hint: The volume of a
spherical shell, lying between radii r and r + dr, is dv = 4(pie)r2dr.
 
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