Imagine you would have to put a rope around the moon. Since the moon is 1,738,000 metres in diameter, this is a hard task. Finally you have managed to get the rope around the moon but... it is one meter short.

You decide to dig a groove all around the moon, so that the shorter rope suffices. How deep must this groove be? (Assume the Moon to be a perfect sphere.)

Moons perimeter = 1,738,000*Pi = 5460088.03194 mts
Rope = 5460088.03194 - 1 = 5460087.03194 mts
New diameter = 5460087.03194/Pi = 1737999.68169 mts

Groove's depth = (1,738,000 - 1737999.68169)/2 = .159155 mts

Posted by Antonio on 2003-08-24 03:16:48