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# Help me mathletes!

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# Help me mathletes!

05-18-08, 06:32 PM
#1
the pope
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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.

Thanks!
05-18-08, 06:36 PM
#2
sp00ki
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1) pencil
2) paper
3) ruler
4) protractor

surely you have these...
05-18-08, 06:38 PM
#3
the pope
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What's a protractor?
05-18-08, 06:44 PM
#4
sp00ki
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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.
05-18-08, 06:45 PM
#5
the pope
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Oh, sweet idea. Thanks.
05-18-08, 06:48 PM
#6
Peedtm
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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.
05-18-08, 06:49 PM
#7
the pope
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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.
05-18-08, 07:02 PM
#8
Peedtm
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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.
05-18-08, 07:34 PM
#9
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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.
05-18-08, 07:40 PM
#10
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Smarties.
05-18-08, 08:23 PM
#11
dervish
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05-18-08, 11:49 PM
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Originally Posted by the pope
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.

Thanks!
Type this: 23*sin(2*pi*5/360) to google search box and mouse over to get 2 cm and a change.
05-19-08, 01:11 AM
#13
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05-19-08, 01:41 AM
#14
vobopl
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Originally Posted by raster
someone got bored with 80% project

Last edited by vobopl; 05-19-08 at 02:11 AM.
05-19-08, 08:33 AM
#15
kemmer
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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.
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05-19-08, 08:51 AM
#16
vobopl
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How about unit conversions (inches to metric etc.) paste that: 20 inches in cm and mouse over
05-19-08, 10:50 AM
#17
Yoshi
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But can google do Gauss-Jordan elimination?
05-19-08, 11:20 AM
#18
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Originally Posted by Yoshi
But can google do Gauss-Jordan elimination?
No but it finds online calculators for linear algebra!
05-19-08, 01:23 PM
#19
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can google do statics? not statistics, statics

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