The111 1 #51 January 9, 2004 Quotesince you've thrown deities into the discussion... the gods (or nature in this case) simply doesnt work in decimal numbers. thats why we have strange things like Pi, e, "goldne ratio number" and all kinds of physical constants... its not God's mistake, its our estimation of nature's perfection... Actually, if God does not think in decimal but created beings with 10 digits that they would use to create a counting system, then he did make a mistake. www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
lummy 4 #52 January 9, 2004 QuoteLang may your lum reek! Hmmm... I'm not sure if I should take offense to thatI promise not to TP Davis under canopy.. I promise not to TP Davis under canopy.. eat sushi, get smoochieTTK#1 Quote Share this post Link to post Share on other sites
The111 1 #53 January 9, 2004 Quote "Strain" is defined as change in length divided by original length. Take a sample of stretchy material Original length = 1 unit stretch until 2 units long strain = (2-1)/1 = 1, call this strain1 The sample length is now 2 units. Give it to someone else and ask them to stretch the sample until it's 4 units long: they comply they give it a strain of (4-2)/2 = 1 = strain2 Sum of strains given = strain1 + strain2 = 1+1 =2 Overall strain from beginning to end of exercise is (4-1)/1 = 3 Hence 2=3 so 2-1 = 3-1 or 1=2 QED no division by zero involved. What is QED? Strain2 is not 1. The change in length is (4-2), yes, but assuming the piece is elastic (and you are still in the elastic range at 1, 2, and 4 inches), then it still has an UNDEFORMED length of 1, regardless of the fact that you were holding it at 2 before the second stretch. Strain2 = (4-2)/1 = 2.www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
rehmwa 2 #54 January 9, 2004 QuoteStrain2 is not 1. The change in length is (4-2), yes, but assuming the piece is elastic (and you are still in the elastic range at 1, 2, and 4 inches), then it still has an UNDEFORMED length of 1, regardless of the fact that you were holding it at 2 before the second stretch. Strain2 = (4-2)/1 = 2. Nice, I missed that ... Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants Quote Share this post Link to post Share on other sites
kallend 2,118 #55 January 9, 2004 QuoteQuote "Strain" is defined as change in length divided by original length. Take a sample of stretchy material Original length = 1 unit stretch until 2 units long strain = (2-1)/1 = 1, call this strain1 The sample length is now 2 units. Give it to someone else and ask them to stretch the sample until it's 4 units long: they comply they give it a strain of (4-2)/2 = 1 = strain2 Sum of strains given = strain1 + strain2 = 1+1 =2 Overall strain from beginning to end of exercise is (4-1)/1 = 3 Hence 2=3 so 2-1 = 3-1 or 1=2 QED no division by zero involved. What is QED? Quod erat demonstrandum. Quote Strain2 is not 1. The change in length is (4-2), yes, but assuming the piece is elastic (and you are still in the elastic range at 1, 2, and 4 inches), Quote Didn't say it was elastic. False assumption on your part. It was superplastic. As far as person 2 is concerned, he is given a piece of stuff of length 2 and stretches it to length 4 without being aware of any previous history. Even microstructural examination of a superplastic alloy gives no information about previous history. The only possible strain he can compute is the strain he gives it, which is (4-2)/2 then it still has an UNDEFORMED length of 1, regardless of the fact that you were holding it at 2 before the second stretch. Strain2 = (4-2)/1 = 2.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kallend 2,118 #56 January 9, 2004 QuoteQuoteLang may your lum reek! Hmmm... I'm not sure if I should take offense to that It's a Scottish good luck wish for the new year.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
lummy 4 #57 January 9, 2004 Ahhhhh.... thanks for the clarification. Ya know, that might help me figure out some things in answer to the "but you're not Chinese and Lum is a Chinese name" questions... Off to Google!!!I promise not to TP Davis under canopy.. I promise not to TP Davis under canopy.. eat sushi, get smoochieTTK#1 Quote Share this post Link to post Share on other sites
The111 1 #58 January 9, 2004 So where's the mistake that causes the inequality at the end?www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
kallend 2,118 #59 January 9, 2004 QuoteSo where's the mistake that causes the inequality at the end? The definition of strain is such that finite strains cannot be meaningfully added. Infinitesimal strains can be added.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
