# Determine the density of a planet in SI units

1. Apr 24, 2012

### surfingian

1. The problem statement, all variables and given/known data
Determine the density of fictional planet in SI units from the information

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

3. 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.

2. Apr 24, 2012

### tiny-tim

welcome to pf!

hi surfingian! welcome to pf!

density is per volume

3. Apr 24, 2012

### MrWarlock616

The radius is not the volume. $Volume=\frac{4}{3} \pi r^3$

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