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Rope puzzle

Discussion in 'General Discussion' started by 2scoops0406, 18 Jan 2009.

  1. 2scoops0406

    2scoops0406

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    Here's another one but with far less safety implications (I may have lifted this from this forum so apologies if I have)

    Assume the earth is a perfect sphere. You have a rope that stretches arounf the equator so the the ends of the rope just touch.

    Now you want the same rope to be uniformly suspended 1 foot above the surface, how much extra rope do you need?
     
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  3. blondini

    blondini

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    That ones as easy as pi
     
  4. 2scoops0406

    2scoops0406

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    If your saying it's pi feet, then I'm sorry, that's not correct. :D
     
  5. 2scoops0406

    2scoops0406

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    Well sorry about not being intuitive, the point is well made, in that I had to check the calculation a couple of times as I originally thought I'd made a mistake.
     
  6. Softus

    Softus

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    The answer is (2 * pi) feet.
     
  7. 2scoops0406

    2scoops0406

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    Correct.
     
  8. blondini

    blondini

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    I see my enlargement on my pie joke has been removed :rolleyes:
     
  9. 2scoops0406

    2scoops0406

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    My fault, hijacked a post.
     
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  11. peteftw

    peteftw

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    sorry to get in a bit late on this one, are you saying the rope only has to be 6' longer?
     
  12. tim west

    tim west

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    what if it's bungee rope?
     
  13. blondini

    blondini

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    Close. Just two times the value of pi.

    (1' extra radius = 2' extra circumference...)
     
  14. Softus

    Softus

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    Huh?
     
  15. blondini

    blondini

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    Uhuh.
     
  16. Softus

    Softus

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    I beg to differ.
     
  17. peteftw

    peteftw

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    so what if it was round the circumferance of an elephants belly would it still need to be 6' longer to hover 1'?
     
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