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Question

Assume the world is a spherical planet with a diameter of 1600 km with a uniform density of 5200 kilograms per cubic metre. If the moon is in a geostationary orbit around the Earth, and assuming a Earth sidereal day is exactly 24 hours, how far is that geostationary orbit above the surface of Earth?

Answer 1

see: http://en.wikipedia.org/wiki/Geosynchron...

Answer 2

The actual text of this week's Neopets "Lenny Conundrum" contest puzzle (Round 271) is as follows:

"Assume the world of Neopia is a spherical planet with a diameter of 1600 km with a uniform density of 5200 kilograms per cubic metre. If the moon of Kreludor is in a geostationary orbit around Neopia, and assuming a Neopian sidereal day is exactly 24 hours, how far is that geostationary orbit above the surface of Neopia?"

To obtain the prize-winning answer value for this latest Neopets "Lenny Conundrum" contest puzzle, try following the instructions here:

http://lennyconundrumsolutions.blogspot....