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  1. #1
    Senior Member the pope's Avatar
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    Help me mathletes!

    Question from the back of the class:

    Word problem.

    A flat bar, 46 centimeters long with a 5 degree sweep, will sweep back how many centimeters from the center to an end. I realize that the sweep in a flat bar does not start in the center but I've shortened the measuring distance to (hopefully reasonably accurately) compensate for this.

    I'm pitiful. Please help.

    Thanks!

  2. #2
    partly metal, partly real sp00ki's Avatar
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    1) pencil
    2) paper
    3) ruler
    4) protractor

    surely you have these...
    Quote Originally Posted by bonechilling View Post
    Road [racing] is one of the only sports where adult men can compete in a non-scholastic setting, so inevitably 8/10 racers are fiercely-competitive nobodies. It's fun as hell, but it's also the foremost refuge of defeated and aging jocks, turned middle-management types.

  3. #3
    Senior Member the pope's Avatar
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    What's a protractor?

  4. #4
    partly metal, partly real sp00ki's Avatar
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    it's a simple tool which allows you to draw angles.

    if you have a printer:
    1) type pdf protractor into google
    2) print it out
    3) make a dot where the anchor point is
    4) make a dot where the 5 is and another where 0 is
    5) draw a line from the anchor dot to the 5 dot; another from the anchor to 0

    the line from anchor to the 5 dot is a 5 degree sweep. draw a 46mm (or whatever) line from the anchor through the 5 with a ruler. that's half the length of your bar. the rest should work itself out as you go.
    Quote Originally Posted by bonechilling View Post
    Road [racing] is one of the only sports where adult men can compete in a non-scholastic setting, so inevitably 8/10 racers are fiercely-competitive nobodies. It's fun as hell, but it's also the foremost refuge of defeated and aging jocks, turned middle-management types.

  5. #5
    Senior Member the pope's Avatar
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    Oh, sweet idea. Thanks.

  6. #6
    Tell them I hate them Peedtm's Avatar
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    Put the flat part against a wall and measure from the wall to whatever part you're curious about

    Edit: Or solve tan(x/23)= pi/36 (5 degrees in radians)
    Last edited by Peedtm; 05-18-08 at 06:52 PM.
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  7. #7
    Senior Member the pope's Avatar
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    I don't have the part yet. Wondering if I'll need a longer stem - and how much longer.

    Measured. At 25 cm length I get a rise of 2 cm. That's a ballpark.

  8. #8
    Tell them I hate them Peedtm's Avatar
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    If you consider the slope (from math, 'member?) is pi/36, this is ~.087 cm of rise per cm of run. If you extend that for 25 cm (25 X .087), that equals 2.175cm. So I concur, sir. Go to it.
    If you want to know about Tarck Bikes, PM me.
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  9. #9
    big ring MIN's Avatar
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    sin(5)*(46/2)=~2cm of backsweep

    this translates to about 1.5cm in extra stem reach requirement because in reality hand placement is not at the end of the bar but about 5cm from the end.

  10. #10
    Senior Member the pope's Avatar
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    Smarties.

  11. #11
    unofficial
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    dont feel bad, im bad at math too
    dj: 09 eastern night train 26
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  12. #12
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    Quote Originally Posted by the pope View Post
    Question from the back of the class:

    Word problem.

    A flat bar, 46 centimeters long with a 5 degree sweep, will sweep back how many centimeters from the center to an end. I realize that the sweep in a flat bar does not start in the center but I've shortened the measuring distance to (hopefully reasonably accurately) compensate for this.

    I'm pitiful. Please help.

    Thanks!
    Type this: 23*sin(2*pi*5/360) to google search box and mouse over to get 2 cm and a change.

  13. #13
    Heck yes. raster's Avatar
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    Wait. Google does math too!?
    Quote Originally Posted by elTwitcho View Post
    You stop and go in your bag about 40-50+ times per day riding across the city over an 8 hour period?

    Are you a drug dealer?

  14. #14
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    Quote Originally Posted by raster View Post
    Wait. Google does math too!?
    someone got bored with 80% project
    Last edited by vobopl; 05-19-08 at 02:11 AM.

  15. #15
    *****es love tarck kemmer's Avatar
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    Holy ****, that's amazing. Google is totally going to take over the universe. Maybe this is how the trade federation starts.

  16. #16
    re:member
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    How about unit conversions (inches to metric etc.) paste that: 20 inches in cm and mouse over

  17. #17
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    But can google do Gauss-Jordan elimination?

  18. #18
    big ring MIN's Avatar
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    Quote Originally Posted by Yoshi View Post
    But can google do Gauss-Jordan elimination?
    No but it finds online calculators for linear algebra!

  19. #19
    SWAAAAAAAAAAAT
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    can google do statics? not statistics, statics
    once you go tarck, you never go barck

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