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You are not logged in. #3 20060220 05:01:27
Re: Surfaces of RevolutionMy book never discussed surface area of solids of revolution. I have a few idea's for how it might be accomplished but I've never tried. Maybe I should... A logarithm is just a misspelled algorithm. #8 20060220 05:34:04
Re: Surfaces of RevolutionYes you will and the formula I posted above multiplies the the average circumference of the rim by the change in arc length over that same distance. Note that like the disk or washer method for calculating volumes that the formula above rotates about the same axis as the variable! Last edited by irspow (20060220 05:35:29) #9 20060220 05:45:07
Re: Surfaces of Revolutionlol. MS paint. I just drew two ellipses, connected the lines and filled in color to make it look how I wanted. A logarithm is just a misspelled algorithm. #10 20060220 05:52:46
Re: Surfaces of RevolutionReally? Okay, I can play around with that. I haven't tried to much with paint even though it has been out forever. Honestly, I really never used it for much more than image manipulation, because the tools are soooo limited. I obviously am too cheap to go out and buy a decent software program. Thanks anyway. #12 20060220 06:28:27
Re: Surfaces of RevolutionAnd if you have a shape of known cross section, the integral becomes much simpler. El que pega primero pega dos veces. #13 20060220 07:02:09
Re: Surfaces of RevolutionYou've got me ryos. I don't even know why you would bother using a third coordinate. It looks like the figure you have there can be described by boundaries in just the x and y axis. The way you are describing it, I don't even think that revolutions of solids is appropriate. Three dimensional calculus is seperate from what we are talking about here. The formula we are using here is derived based on a two dimensional analysis. I would dig into vector or multivariable calculus to solve it in the terms that you want to use. 