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Perfect circle.

  1. Apr 17, 2005 #1
    Is it possible to draw a perfect circle. My answer wold be no, because the perimeter of the circle should be a multiple of pi, but pi is transcendent, so it is not posibble. Am i right?
  2. jcsd
  3. Apr 17, 2005 #2


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    No.The transcendental character of [itex] \pi[/itex] has nothing to do with the geometry involved in picking a compasses and drawing that circle.

  4. Apr 17, 2005 #3
    I dont believe a 'perfect' circle is possible, but it depends onwhat you mean by perfect.
  5. Apr 17, 2005 #4
    I think he means a perfect physical circle. In that case, the answer is no.
  6. Apr 17, 2005 #5
    Actually there are limits to 'perfection'..but as 'good as' is achievable in some instances, example..I was told by someone in high mathematical regard, that it was known from ancient times that the Greek Philosophicals regarded 'perfection' as a human unatainable achievement, he refered to someone (I cant recall who?) that was set a task to produce the perfect circle, "physical drawing of". I immeidiatley went to the blackboard, chalk in hand, and proceeded to attempt the immposible.

    I approached the blackboard, stood in front, the I turned at an angle of 45 degree's, so My shoulder was touching the blackboard. I then proceeded to use my shoulder as the 'point' of the compass, turning my arm around, I produced..a near as damn it pefect circle! :wink:

    Try it and step back from the blackboard and observe your attempt?
  7. Apr 17, 2005 #6
    The simplest mechanical linkage that produces a straight line motion, Peucillier's inversor, relies on circular motion. So the straightest line you can draw is only as perfect as the best circle you can draw, or maybe less so.
  8. May 12, 2009 #7
    ah, but it is only what you percieve, (<-----is that how you spell it?)
    it is not truly "perfect"
    which, nowadays is a loosly thrown around term.
  9. May 12, 2009 #8


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    thread locked
    Necropost replying to a banned member, therefore pointless.
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