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## Homework Statement

A satellite is in a circular orbit very close to the surface of a spherical planet. The period of the orbit is 2.49 hours.

What is density of the planet? Assume that the planet has a uniform density.

## Homework Equations

T^2 = (4(pi)^2*r^3) / GM

## The Attempt at a Solution

Okay, so I coverted the period into seconds and got 8964 seconds.

Then I rearranged the equation to get

M/r^3 = 4(pi)^2 / GT^2, assuming that M/r^3 would get me density.

So then according to that Density = 4(pi)^2 / (6.67e-11 N*m^2/kg^2)(8964 s)^2 which gives 7366 kg/m^3 which is not correct.

Or am I missing something about density? Density is mass divided by area. Should I be finding a radius to find the area and then find the mass somehow... I don't know. I'm confused on what to do.