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#1




how to figure circumfrence (sp)
knowing that the diameter of a circle is 32 and 1/2 inches, How do I
figure the outside length of the disk. TIA moyo 
#2




On Tue, 17 Aug 2004 01:14:50 +0000, moyo wrote:
knowing that the diameter of a circle is 32 and 1/2 inches, How do I figure the outside length of the disk. Pi times the diameter. Two times pi times the radius. Pi is 3.141592654 (Pi has infinite digits beyond the decimal, but your calculator doesn't care.) 102.1 inches.  "Keep your ass behind you" 
#3




moyo wrote:
knowing that the diameter of a circle is 32 and 1/2 inches, How do I figure the outside length of the disk. TIA moyo ( Ð¿ = 3.1415926535897932384626433832795 [approximately]) C = Ð¿ Â· D = Ð¿ Â· 32.5 = 102.10176124166828025003590995658 [approximately]  Morris Dovey DeSoto, Iowa USA 
#4




"Morris Dovey" wrote in message C = ? · D = ? · 32.5 = 102.10176124166828025003590995658 [approximately]  Morris Dovey DeSoto, Iowa USA Ya, but my ruler is not able to read that close. Why not just round it off to a more realistic number like 102.10176124166828? 
#5




Edwin Pawlowski wrote:
"Morris Dovey" wrote in message C = ? · D = ? · 32.5 = 102.10176124166828025003590995658 [approximately] Ya, but my ruler is not able to read that close. Why not just round it off to a more realistic number like 102.10176124166828? Can if you want to  but I have standards to maintain! Just imagine the horrible consequences of an only 0.00000000000000025003590995658" gap in a tinfoil helmet...  Morris Dovey DeSoto, Iowa USA 
#6




On Mon, 16 Aug 2004 20:24:10 0500, Australopithecus scobis
wrote: Pi times the diameter. Two times pi times the radius. Pi is 3.141592654 (Pi has infinite digits beyond the decimal, but your calculator doesn't care.) 102.1 inches. 102 3/32 for those without decimal rulers. Bill. 
#7




My, My....thats an awfully big pi...
"Australopithecus scobis" wrote in message news On Tue, 17 Aug 2004 01:14:50 +0000, moyo wrote: knowing that the diameter of a circle is 32 and 1/2 inches, How do I figure the outside length of the disk. Pi times the diameter. Two times pi times the radius. Pi is 3.141592654 (Pi has infinite digits beyond the decimal, but your calculator doesn't care.) 102.1 inches.  "Keep your ass behind you" 
#8




See a Rabbi.
Oh, that's something else, nevermind... 
#9




"David F. Eisan" wrote in message et.cable.rogers.com... See a Rabbi. Oh, that's something else, nevermind... How long is a mohel? 
#10




"Mark Hopkins" wrote in message ... My, My....thats an awfully big pi... Pi are not square. Pi are round. Cake are square. Is this the world's oldest math joke? Bob 
#11




On Tue, 17 Aug 2004 05:56:37 0400, "Mark Hopkins"
vaguely proposed a theory .......and in reply I say!: remove ns from my header address to reply via email My, My....thats an awfully big pi... wi? 102.101761241668280250035909956584 "Keep your ass behind you" Iiiii Knoooowwwww! My donkey kicked me in the behind just the other day.... ************************************************** *** Marriage. Where two people decide to get together so that neither of them can do what they want to because of the other one. 
#12




On Tue, 17 Aug 2004 11:11:27 GMT, "David F. Eisan"
vaguely proposed a theory .......and in reply I say!: remove ns from my header address to reply via email There is a fate that shapes our ends, rough hew them though we may..... See a Rabbi. Oh, that's something else, nevermind... You use the term "figure" very well, m'sieur. ************************************************** *** Marriage. Where two people decide to get together so that neither of them can do what they want to because of the other one. 
#13




"Bob Schmall" wrote in message ... "David F. Eisan" wrote in message et.cable.rogers.com... See a Rabbi. Oh, that's something else, nevermind... How long is a mohel? Not sure, but I know I'm short about 4 or 5 inches. I guess they used me as an organ donor. 
#14




On Tue, 17 Aug 2004 11:11:27 GMT, "David F. Eisan"
calmly ranted: See a Rabbi. Oh, that's something else, nevermind... I believe you were referring to theese, Meester Ironmonger: Three Samurai Once upon a time a powerful Emperor advertised for a new Chief Samurai. Only three applied for the job: a Japanese, a Chinese and a Jewish Samurai. "Demonstrate your skills!" commanded the Emperor. The Japanese samurai stepped forward, opened a tiny box, and released a fly. He drew his samurai sword and "swish"; the fly fell to the floor, neatly divided in two! "What a feat!" said the Emperor. "Number Two Samurai, show me what you cando." The Chinese samurai smiled confidently, stepped forward and opened a tiny box, releasing a fly. He drew his samurai sword and "swish, swish"; the fly fell to the floor, neatly quartered! "That is skill!" nodded the Emperor. "How are you going to top that, Number Three Samurai?" Number Three Samurai stepped forward, opened a tiny box, released one fly, drew his Samurai sword, and "swoooooosh" flourished his sword so mightily that a gust of wind blew through the room. But the fly was still buzzing around! In disappointment, the Emperor said, "What kind of skill is that? The fly isn't even dead." "Dead, schmed," replied the Jewish Samurai. "Dead is easy. CircumcisionTHAT takes skill!" /Three Samurai ============================================ Growing old is mandatory; growing up is optional.  http://diversify.com Comprehensive Website Development 
#15




On Tue, 17 Aug 2004 13:49:35 GMT, "Bob Schmall"
calmly ranted: "David F. Eisan" wrote in message . net.cable.rogers.com... See a Rabbi. Oh, that's something else, nevermind... How long is a mohel? Is that what you're making this mountain out of, Bob? ============================================ Growing old is mandatory; growing up is optional.  http://diversify.com Comprehensive Website Development 
#16




Now if you live in Indiana, you can simplify
your Pi calculations. If you've never heard this story, it's an interesting read: http://www.agecon.purdue.edu/crd/Loc...0pages/Indiana _Pi_Story.htm Lou 
#17




loutent wrote:
Now if you live in Indiana, you can simplify your Pi calculations. If you've never heard this story, it's an interesting read: http://www.agecon.purdue.edu/crd/Loc...0pages/Indiana _Pi_Story.htm Lou... Interesting read. About that same time there were a number of states who considered similar legislation; and (I've heard but haven't confirmed) at least one state who actually enacted a statute defining pi to be exactly three.  Morris Dovey DeSoto, Iowa USA 
#18




"Morris Dovey" wrote in message ...   and (I've heard but haven't confirmed) at least one state who  actually enacted a statute defining pi to be exactly three. Tennessee, and only in Robert Heinlein's "Stranger in a Strange Land." It didn't actually happen. The Indiana story is true enough, but it has spawned numerous spurious copycat stories that are standard April Fool's Day fare. Heinlein's is just the most immediately credible. The state in question is always some state presumed inhabited by rustics. But no state in the U.S. has ever had a law passed legislating the value of pi. Indiana came close. Jay 
#19




Jay Windley wrote:
Tennessee, and only in Robert Heinlein's "Stranger in a Strange Land." It didn't actually happen. The Indiana story is true enough, but it has spawned numerous spurious copycat stories that are standard April Fool's Day fare. Heinlein's is just the most immediately credible. The state in question is always some state presumed inhabited by rustics. But no state in the U.S. has ever had a law passed legislating the value of pi. Indiana came close. Whew! That's definitely reassuring. (:  Morris Dovey DeSoto, Iowa USA 
#20




On Wed, 18 Aug 2004 08:37:08 0400, loutent vaguely
proposed a theory .......and in reply I say!: remove ns from my header address to reply via email 100 seconds to the hour, ten hours per day, 100 days per year. All this would be possible, if only we could round off Pi. Now if you live in Indiana, you can simplify your Pi calculations. If you've never heard this story, it's an interesting read: http://www.agecon.purdue.edu/crd/Loc...0pages/Indiana _Pi_Story.htm Lou ************************************************** *** Marriage. Where two people decide to get together so that neither of them can do what they want to because of the other one. 
#21




On Wed, 18 Aug 2004 12:19:27 0600, Jay Windley wrote:
"Morris Dovey" wrote in message ...   and (I've heard but haven't confirmed) at least one state who  actually enacted a statute defining pi to be exactly three. Tennessee, and only in Robert Heinlein's "Stranger in a Strange Land." It didn't actually happen. The Indiana story is true enough, but it has spawned numerous spurious copycat stories that are standard April Fool's Day fare. Heinlein's is just the most immediately credible. The state in question is always some state presumed inhabited by rustics. But no state in the U.S. has ever had a law passed legislating the value of pi. Indiana came close. I annoyed my HS geometry teacher by announcing I could trisect an angle. True, a Carpenter's Square is illegal under the rules of "Geometric Construction", but I could easily prove that it worked. There are other methods, using other tools, but a carpenter's square is probably the easiest to prove correct. 
#22




"UCDK_CHARLES\Charles" "Charles wrote in message news:j_5Vc.15253$Zh3.2575@trndny02...  On Wed, 18 Aug 2004 12:19:27 0600, Jay Windley wrote:   There are other methods, using other tools, but a carpenter's square is  probably the easiest to prove correct. Hence the original masons used three tools: the straightedge, the compass, and the square. It's amazing what you can do with those tools and a little "secret" geometretic knowledge.  Jay 
#23




Ken McIsaac wrote:
Unfortunately, I have learned that I can do the math, but I can not cut these crazy dimensions accurately. From now on, it's 90 degrees or 45 degrees or redesign it because it's wrong. I had the same problem. You can solve (most) such problems with a CNC router; but it's a tad spendy if you're not serious about making it pay its own way.  Morris Dovey DeSoto, Iowa USA 
#24




On Thu, 19 Aug 2004 12:31:22 0600, "Jay Windley"
wrote: "UCDK_CHARLES\Charles" "Charles wrote in message news:j_5Vc.15253$Zh3.2575@trndny02...  On Wed, 18 Aug 2004 12:19:27 0600, Jay Windley wrote:   There are other methods, using other tools, but a carpenter's square is  probably the easiest to prove correct. Hence the original masons used three tools: the straightedge, the compass, and the square. It's amazing what you can do with those tools and a little "secret" geometretic knowledge. I'm still a neophyte, but I'm increasingly reaching the conclusion that a little geometric knowledge is all you *want* to have. Because of a misspent youth, I can do a lot of what people tell me is fairly complex mathematics in my head. So I wind up designing furniture that contains 18.7457 degree angles, or better yet, angles that are arctan(5.75/11) or lengths that are (5+sqrt(7))/2 or something. I actually computed a fifth order polynomial approximation to the chair leg curve I wanted on a table I made for my motherinlaw last year. Unfortunately, I have learned that I can do the math, but I can not cut these crazy dimensions accurately. From now on, it's 90 degrees or 45 degrees or redesign it because it's wrong.  Jay 
#25




On Mon, 23 Aug 2004 16:47:43 0400, Ken McIsaac
wrote: I actually computed a fifth order polynomial approximation to the chair leg curve I wanted on a table I made for my motherinlaw last year. That one I'd like to see. Unfortunately, I have learned that I can do the math, but I can not cut these crazy dimensions accurately. From now on, it's 90 degrees or 45 degrees or redesign it because it's wrong. Then your own designs are fairly simple. I admire people who do their own design. It's not the math, it's art. The math I can do easily, and often apply it in the shop, or on the computer or wherever, but the art? Stick people are beyond me. I need plans with numbers on them mostly. I did figure out how IKEA designed their neat folding table though. Bill. 
#26




Ken McIsaac wrote:
It's not quite that my designs are simple. It's just that I have to take my original crazy designs and simplify them until they contain no parts that I can't make. Right now, that means it has to require no skill. I need a fence or guide or something to follow or the results are not pretty. I understand from my reading that people typically cut curves by following a hardboard template. I'm not sure how this solves the problem, since you first have to get the template right. Plot your design. You can either superimpose it on a grid and scale it; or you can find a way to plot it full size. If necessary run it out on your printer in pieces, one piece per page, and then tape the printed pieces together... Now you can transfer the design to the hardboard. Did you know that you can get hardboard with a slick white surface at the lumberyard?) I have a piece tacked to the wall that I sketch on with dry erase markers  lets me redraw to my heart's content. Practise makes (more) perfect. (:  Morris Dovey DeSoto, Iowa USA 
#27




On Mon, 23 Aug 2004 19:29:09 0400, Bill Rogers
wrote: On Mon, 23 Aug 2004 16:47:43 0400, Ken McIsaac wrote: I actually computed a fifth order polynomial approximation to the chair leg curve I wanted on a table I made for my motherinlaw last year. That one I'd like to see. I knew the shape I wanted, but I can't draw (as you say, stick people are also beyond me), so the only way I could represent it was mathematically. I wanted the leg to be two inches wide at the top, one inch wide at the bottom and oneandahalfinch wide halfway down. I also knew I wanted the first derivative to be zero at the top and at the bottom, and I wanted the second derivative to be zero halfway down. That's enough to define a fifth order polynomial. The fun part was going to be to try to do it on two faces of the leg to get the threedimensional shape I wanted. So I got out Matlab and plotted the thing, then I tried to draw it on the leg with a pencil. Then I contemplated actually cutting it with my crappy jigsaw. Then I decided my mother in law would be very happy with a tapered leg. Then your own designs are fairly simple. It's not quite that my designs are simple. It's just that I have to take my original crazy designs and simplify them until they contain no parts that I can't make. Right now, that means it has to require no skill. I need a fence or guide or something to follow or the results are not pretty. I understand from my reading that people typically cut curves by following a hardboard template. I'm not sure how this solves the problem, since you first have to get the template right. I have also learned that two or three hours with coarse sandpaper can make anything look good. 
#28




On Tue, 24 Aug 2004 11:26:03 0400, Ken McIsaac
wrote: actually computed a fifth order polynomial approximation to the chair leg curve I wanted on a table I made for my motherinlaw last year. That one I'd like to see. I knew the shape I wanted, but I can't draw (as you say, stick people are also beyond me), so the only way I could represent it was mathematically. I wanted the leg to be two inches wide at the top, one inch wide at the bottom and oneandahalfinch wide halfway down. I also knew I wanted the first derivative to be zero at the top and at the bottom, and I wanted the second derivative to be zero halfway down. That's enough to define a fifth order polynomial. The fun part was going to be to try to do it on two faces of the leg to get the threedimensional shape I wanted. I won't dwell on it, but you still lose me. A 5th degree polynomial has [at most] four local max/min; i.e. the plot goes up/down/up/down/up. That's a strange shape for a leg. :) So I got out Matlab and plotted the thing, then I tried to draw it on the leg with a pencil. Matlab is a bit hefty for that sort of thing. Try Graphmatica for 2D plots: www,archives.math.utk.edu. I find DeltaCad really helpful. A bit of a learning curve for a drawing klutz like myself, but I finally got the hang of doing spline curves. Bill. 
#29




On Tue, 24 Aug 2004 13:16:22 0400, Bill Rogers
wrote: I won't dwell on it, but you still lose me. A 5th degree polynomial has [at most] four local max/min; i.e. the plot goes up/down/up/down/up. That's a strange shape for a leg. :) The trick is the "at most". I just wanted flat at both ends and the curve in between equally distributed. At the risk of dwelling on it: f(x)=6x^5  15x^4 + 10x^3 between x=0 and x=1 is the function I settled on. I think it'sa fairly standard chair leg shape, actually, although I don't know the name of it. The up/down/up/down/up part happens outside the range of interest. It's not as strange as all that, and I probably could have achieved the same thing with a set of french splines. This way, I got to tell myself I was "woodworking" when what I was actually doing was playing with Matlab. I got to have similar fun when I sat down to plan the angle I needed to cut a desired cove on my table saw. As always, the doing was much harder than the math. I find DeltaCad really helpful. A bit of a learning curve for a drawing klutz like myself, but I finally got the hang of doing spline curves. I did find myself a cheap (free) CAD package, but I found it very hard to use. My (minimal) CAD training is 15 years old, and at that time, you typed in the coordinates of the points you wanted and the machine drew it for you. These days, apparently, it's all about starting with blank shapes and doing cutting planes or rotations on them. This is not how my brain works at all. Bill. 
#30




On Tue, 24 Aug 2004 15:10:46 0400, Ken McIsaac
wrote: The trick is the "at most". I just wanted flat at both ends and the curve in between equally distributed. At the risk of dwelling on it: f(x)=6x^5  15x^4 + 10x^3 between x=0 and x=1 is the function I settled on. Neat!! It's not as strange as all that, and I probably could have achieved the same thing with a set of french splines. This way, I got to tell myself I was "woodworking" when what I was actually doing was playing with Matlab. I got to have similar fun when I sat down to plan the angle I needed to cut a desired cove on my table saw. As always, the doing was much harder than the math. I use Mupad for something more dramatic, but will stick to simpler programs, usually preferring to figure by hand. My brother in law was a draftsman, and left me some of his tools. One "French curve" is in the shape of a babe. I'm afraid to handle her too much ...too distracting, so she sits in a drawer. I did find myself a cheap (free) CAD package, but I found it very hard to use. My (minimal) CAD training is 15 years old, and at that time, you typed in the coordinates of the points you wanted and the machine drew it for you. These days, apparently, it's all about starting with blank shapes and doing cutting planes or rotations on them. This is not how my brain works at all. Do try Deltacad. It's very intuitive. All have a learning curve, but this one is relatively slight. Recently I drew up a model of our front door that I have to rebuild. Just rectangles and a few lines and dimensions are figured automatically. The end product is infinitely neater than I could draw or sketch. Bill. 
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