perplexus.info :: Shapes : The groove around the moon

The groove around the moon (Posted on 2002-05-06)

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.)

See The Solution Submitted by charl

Rating: 2.9167 (12 votes)

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
A different (and simple) approach	JayDeeKay	2015-06-05 18:08:30
re(2): answer	K Sengupta	2008-06-07 16:32:10
re: answer	Dej Mar	2008-06-07 12:38:51
answer	K Sengupta	2007-05-15 04:19:42
re: Zero Option Solution	owl	2004-10-28 12:42:37
Zero Option Solution	CeeAnne	2004-10-27 15:28:24
Differences	bob909	2004-10-27 09:44:21
re: dig it	prashant	2004-03-29 07:52:16
dig it	prashant	2004-03-29 07:39:08
Solution	Antonio	2003-08-24 03:16:48
No Subject	Lucifer	2003-03-01 09:12:26
No Subject	danny	2002-11-12 17:42:33
You win	Mike	2002-07-24 22:53:55
re: Got to be wrong!	TomM	2002-07-24 07:34:23
Got to be wrong!	Mike	2002-07-24 05:25:51
My Answer	Tom	2002-05-09 12:47:14
thanks	John Ryder	2002-05-09 08:04:52
Well...	levik	2002-05-08 20:22:10
I understand what you're saying...but	John Ryder	2002-05-08 13:08:49
Look at it this way	levik	2002-05-08 11:34:48
I don't understand the Solution	John Ryder	2002-05-08 07:11:38
Solution	Stuff N. Things	2002-05-07 17:55:53
ring around the WHAT?	Dan Dise	2002-05-07 13:45:41
But....	John	2002-05-07 12:28:11
solution?	John Ryder	2002-05-07 11:45:39
But only...	John	2002-05-07 10:43:32
Interesting observation	Whiskey Pete	2002-05-07 09:29:50
Hmmm...	Tim	2002-05-07 08:59:17
Solution	Terry	2002-05-07 08:58:34
David Rowley Correct	toferc	2002-05-07 07:37:16
Solution?	David Rowley	2002-05-07 07:17:42
1 meter??	kevin	2002-05-07 07:07:13

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