cylinder volume

Discussion in 'Math' started by adamclark, Dec 2, 2013.

  1. adamclark

    Thread Starter Member

    Oct 4, 2013
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    Whats the formula for measuring the volume in cf of a cylinder?
     
  2. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    Area of the base time height. Units in feet.
     
  3. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    volume of a cylinder = pi times radius squared times height
     
    Last edited: Dec 4, 2013
  4. adamclark

    Thread Starter Member

    Oct 4, 2013
    472
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    Im building a woofer box for my car and I have some 12 inch abs pipe. It measures 11 inches i.d. . I need 1.25 cf of air for my woofer. How long would it need to be? I understand your formula ok but how would I find the length it needs to be?
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    11" = 5.5" radius = 0.458'
    3.1416 X .458'² X L = 1.25'³
    1.439' L = 1.25'³
    L = 1.897' or 22.76"

    The volume of 2' long pipe at 11" width is.

    CF = π R² L = 3.1416 X 5.5"² X 24" = 2280.80"³ or 1.32'³

    Be aware though, with any tube of air comes resonance.
     
    Last edited: Dec 3, 2013
  6. WBahn

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    Mar 31, 2012
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    I think you meant "volume" of a cylinder.
     
  7. WBahn

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    Mar 31, 2012
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    Bill, look at your notation. If 5.5"² means to square 5.5" and not 5.5 square inches, then doesn't 2280.80"³ have to mean to cube 2280.80" and not 2280.80" cubic inches?

    Might I suggest:

    CF = π R² L = 3.1416 X (5.5")² X 24" = (2280.80)"³ or (1.32)'³

    or

    CF = π R² L = 3.1416 X (5.5")² X 24" = 2280.80("³) or 1.32('³)

    Probably the best would be to not use the " and ', despite how convenient they are.

    CF = π R² L = 3.1416 X (5.5 in)² X 24 in = 2280.80 in³ or 1.32 ft³
     
    Last edited: Dec 4, 2013
  8. Wendy

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    Mar 24, 2008
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    Picky! At least I used notations! :p :D
     
  9. tracecom

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    Apr 16, 2010
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    Hey, I got the right answer; I just forgot the question. :D
     
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