Determine the density of a planet in SI units

AI Thread Summary
To determine the density of a fictional planet in SI units, the mass of 1.28x10^22 kg must be divided by the volume, not the radius. The correct formula for volume is V = (4/3)πr^3, where r is the radius in meters. The initial calculation mistakenly used the radius instead of the volume, leading to an incorrect density value. Density should be expressed in kg/m³, and the proper calculation will yield the correct result. Clarification on the distinction between radius and volume is essential for accurate density determination.
surfingian
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Homework Statement


Determine the density of fictional planet in SI units from the information


Homework Equations


Planets mass 1.28x10^22 Kg divided by radius 1.12x10^3Km = 1.14x10^25 Kg/m3

The Attempt at a Solution


My answer seems all wrong, the SI unit should be in Kg/m cubed. Is radius equal to the volume as I feel that this is where the calculation went wrong, or maybe what I have got is right.
 
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welcome to pf!

hi surfingian! welcome to pf! :smile:

density is per volume :wink:
 
The radius is not the volume. ##Volume=\frac{4}{3} \pi r^3##
 
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