Okay.

So we’ve got an entirely flat surface that also happens to be the exact same length as the earth’s surface.

If you had one continuous piece of string that went from one end of that flat surface to the other, and on one end there was attached a bell… would you be able to ring the bell by pulling on the other end of string?

  • @[email protected]
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    fedilink
    81 year ago

    c = pi x d

    So, to increase d by 2 meters (cause d = 2 x r), that’s 2 X pi, or 6.28 meters for string?

      • @davidgro
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        31 year ago

        To really emphasize it, the same amount of extra string would be needed if it was instead wrapped around a small marble at first and the diameter expanded by the same amount.

    • @TheActualDevil
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      11 year ago

      So I’m bad at math. Can you explain why we’ve decided to multiply pi by 2? Is there an articulable reason or is it just a rule?

      c+x= pi * (d+2) in this case, right? So where did that multiply pi by 2 come from?

      • @reattach
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        2
        edit-2
        1 year ago

        Distribute the pi on the right side of your equality, and replace c with pi*d:

        c+x = pi*(d+2)

        pid+x = pid + pi*2

        x = pi*2

        To generalize for an height h,

        x = pi2h

        Edit: I did some weird markup, but won’t be fixing it

        • @TheActualDevil
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          21 year ago

          Oh, I see now. I missed some pretty basic math there with that distribution. That makes sense now, thank you!