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.)

circumference 1m less -> diameter 1/pi m less ->
radius = 1/(2*pi) m less ->
depth of groove = 1/(2*pi)

Posted by toferc on 2002-05-07 07:37:16