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Serik
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Homework Statement
What is the average density of rock in the mantle? The Earth's average density is 5500 kg/m^3; the radius of the core is 3490 km; ratio of core density to mantle density is 2.34
Homework Equations
Pc = density core
Pm = density mantle
Pe = density earth
Mm = mass mantle
Mc = mass core
Rm = radius mantle
Pc/Pm = 2.34 so Pc/2.34=Pm
Pm = Mm/(4/3)*pi*Rm^3
Pc = Mc/(4/3)*pi*(3.49E6)^3
Rm = Re - Rc
Assume only the core and mantle compose the earth.
Mc/Vc + Mm/Vm = Me/Ve = Pe = 5500 (?)
The Attempt at a Solution
Pc/2.34 = Pm = (Mc/(4/3)*pi*(3.49E6)^3)/2.34I'm not sure what equation would give me Mc, the mass of the core. My other equation had the radius of the Earth as a variable. I think I'm just missing one equation, but I can't seem to find another relationship.
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