Singlespeed & Fixed Gear - Help me mathletes!

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the pope
05-18-08, 06:32 PM
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!
1) pencil
2) paper
3) ruler
4) protractor
surely you have these...
the pope
05-18-08, 06:38 PM
What's a protractor?
http://mathforum.org/dr.math/gifs/protractor.gif
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.
the pope
05-18-08, 06:45 PM
Oh, sweet idea. Thanks.
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)
the pope
05-18-08, 06:49 PM
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.
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.
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.
the pope
05-18-08, 07:40 PM
Smarties.
dervish
05-18-08, 08:23 PM
dont feel bad, im bad at math too
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.
Wait. Google does math too!?
Wait. Google does math too!?
:love: someone got bored with 80% project
Holy ****, that's amazing. Google is totally going to take over the universe. Maybe this is how the trade federation starts.
How about unit conversions (inches to metric etc.) paste that: 20 inches in cm and mouse over :innocent:
But can google do Gauss-Jordan elimination?
But can google do Gauss-Jordan elimination?
No but it finds online calculators for linear algebra (http://http://www.google.com/search?hl=en&rls=SUNA%2CSUNA%3A2006-37%2CSUNA%3Aen&q=linear+algebra+calculator)!
tx_what_it_do
05-19-08, 01:23 PM
can google do statics? not statistics, statics
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