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July 29, 2014

July 29, 2014

Posted by **Kylie** on Sunday, January 2, 2011 at 4:51pm.

I have no idea how to start this question please help!

- physics -
**bobpursley**, Sunday, January 2, 2011 at 5:16pmIf the planet is uniform density, then the net gravity force is proportional to the volume enclosed by the radius.

1/7 (4/3 PI R^3)=4/3 PI r^3

so r/R= cuberoot 1/7

how far from the surface? H=R-r

H= R(1-cubroot 1/7) check that.

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