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Catnip
04-16-2010, 07:17 PM
If someone can help me figure out the measurements here, I will happily rep them +28 every time I see them post and I can rep.

http://mathcentral.uregina.ca/QQ/database/QQ.02.06/phil1.html

My measurements known are (labelled according to the diagram in the link):

* t = 2.5" diameter
* b = 4" diameter
* w = 14"

I've worked it out, but I'm 90% sure I'm messing up somewhere.

I've gotten:
r = 7.799
R = 12.559
Inner circle = 57 degrees

Just doesn't make sense considering those numbers are pretty much the same as the circumferences.

allout13
04-16-2010, 07:25 PM
If someone can help me figure out the measurements here, I will happily rep them +28 every time I see them post and I can rep.

http://mathcentral.uregina.ca/QQ/database/QQ.02.06/phil1.html

My measurements known are (labelled according to the diagram in the link):

* t = 2.5" diameter
* b = 4" diameter
* w = 14"

I've worked it out, but I'm 90% sure I'm messing up somewhere.

I've gotten:
r = 7.799
R = 12.559
Inner circle = 57 degrees

Just doesn't make sense considering those numbers are pretty much the same as the circumferences.

Im confused...

radius should be half the diameter so...
r=1.25"
R=2"

or am I misunderstanding something?

Catnip
04-16-2010, 07:33 PM
Im confused...

radius should be half the diameter so...
r=1.25"
R=2"
or am I misunderstanding something?

If you were making a 2.5" cylinder and a 4" cylinder, you'd be correct, but when you're doing a truncated cone unfolded, the length of the cone and difference in diameter, changes the arc radius of the arc length that forms the circumference once the shape is rolled into the truncated cone.

98blackcivic
04-16-2010, 07:34 PM
id help but my mind is fried after doing about 100 derivative problems...my minds taking derivatives upon derivatives out of normal things isee around me

allout13
04-16-2010, 07:47 PM
ahhhh

Im getting r=23.333333 R=37.333333
inner circle is 19.29 degrees

according to the page: the outside radius R is simply w more than the inside radius r so the answer you got appears to be way off.

Catnip
04-16-2010, 07:57 PM
ahhhh

Im getting r=23.333333 R=37.333333 Im not sure how accurate this is, but I'll rework it

according to the page: the outside radius R is simply w more than the inside radius r so the answer you got appears to be way off.

*EDIT** I guess I quoted you as you edited your post, LOL

Those numbers look right, actually!

__________________________________________________ __________________________________________________

Roll a piece of paper into a cone, cut the ends off so they sit flat when it's set down on a table or something. Cut the cone down the length of the "height", so that it unfolds like the diagrams on the length. I think you'll understand it a little better.

The radii of the two diameters created, won't be the radii used if you were making two seperate cylinders that didn't taper.

The two radii will be a number bigger than any measurement given, as the length isn't short compared to the taper. If that makes sense.

allout13
04-16-2010, 08:06 PM
I may be way off, but Im bored as fuck. lol
here's my work
http://i74.photobucket.com/albums/i258/allout13/math.jpg

Catnip
04-16-2010, 08:09 PM
That all looks great. I'll check it out when I get a chance to lay it out on a poster board. Better than the numbers I kept getting :goodjob:

Thanks man!

allout13
04-16-2010, 09:25 PM
That all looks great. I'll check it out when I get a chance to lay it out on a poster board. Better than the numbers I kept getting :goodjob:

Thanks man!

no problem!

Catnip
04-18-2010, 01:23 AM
The answer you gave worked perfectly! Thanks again, bro.

CHRISNITTOLO
04-18-2010, 01:25 AM
You're welcome.

FasTech
04-18-2010, 01:26 AM
Learn math, Evan... dumbass. lol.

Catnip
04-18-2010, 01:27 AM
Learn math, Evan... dumbass. lol.

You couldn't scratch your ass hard enough to figure out 4 is the answer to 2+2.

FasTech
04-18-2010, 01:29 AM
You couldn't scratch your ass hard enough to figure out 4 is the answer to 2+2.


How cute... did you think of that yourself? I mean, just hard to believe seeing as how you can't do 4th grade math. lol.

Catnip
04-18-2010, 01:32 AM
How cute... did you think of that yourself? I mean, just hard to believe seeing as how you can't do 4th grade math. lol.

Sorry I was frustrated after trying a few different layouts from my teacher that didn't work? Last I checked, you didn't give an answer, so you have no room to talk.

CHRISNITTOLO
04-18-2010, 01:32 AM
You couldn't scratch your ass hard enough to figure out 4 is the answer to 2+2.

I could. But it wouldn't make much since to do so.

FasTech
04-18-2010, 01:36 AM
Sorry I was frustrated after trying a few different layouts from my teacher that didn't work? Last I checked, you didn't give an answer, so you have no room to talk.

I'm too cool for math. Would have gave you an answer but you can't understand this so you couldn't understand my answer. See what I did thar.

FasTech
04-18-2010, 01:36 AM
Evan, BTW repped, cause you're that much of a smartass/ lol

Catnip
04-18-2010, 01:38 AM
I'm too cool for math. Would have gave you an answer but you can't understand this so you couldn't understand my answer. See what I did thar.

I see you're also too cool for proper grammar.

lol

CHRISNITTOLO
04-18-2010, 01:53 AM
I'm about to fucking reply to all the threads with my face if I don't get off and go to sleep. Goodnight, guys.