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You are not logged in. Pages: 1 #1 20100912 08:58:57
Need volume of hole removed from hollow cylinder with 5" thick wallI also want to know how to work this problem. #2 20100912 15:22:34
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHi dude; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20100912 22:28:00
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHey BobbyM. Thanks for replying. That answer is incorrect. You used PI * r^2 * h => PI * 144 * 5 => 720 PI #4 20100913 02:56:33
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHi dude; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #5 20100913 04:27:53
Re: Need volume of hole removed from hollow cylinder with 5" thick wall
I call them domes but they are not. Notice I have a cylinder and those equations are fora sphere. No problem to calculate volume for domes cut from a sphere. Much different on a cylinder wall because the top view cross section is a bit misleading. Remember, I am cutting a circular hole through the cylinder wall. #7 20100914 13:18:13
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHi dude; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #9 20100915 13:45:31
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHi dude; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #10 20101114 15:46:25
Re: Need volume of hole removed from hollow cylinder with 5" thick wallThis is a difficult problem, but I think I have come up with the answer (hopefully). In this case, the x will serve as one of the sides of the rectangle. For the 58" cylinder we have the relation The height of the rectangle will be the part of h which is part of the 'cap' above the cylinder which is above 26.40075756. We need the formula for the rectangle in terms of y since we will be integrating with respect to y, so we end up with for the area of the rectangle. The integral will be from 0 to 12 and will be only 1/4 of the volume. So the volume is equal to Can anybody here integrate this? I don't know how to integrate this so I cheated and used a computer program. Now this is only the 'cap' so we need to add this to the cylinder which is So the total volume is Now we do the same thing with the smaller cylinder Total volume is So the volume of removed material is This is close to Bobbym's estimate of Last edited by Fruityloop (20101114 16:16:43) The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. #11 20101114 18:15:59
Re: Need volume of hole removed from hollow cylinder with 5" thick wallHi Fruityloop;
bobbym's estimates are doodly doo! Hope that was not too strong a wording. All that numerical analysis has rotted his brain, yesterday I caught him bounding 7 * 13. He said it was greater than 90 but less than 100. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. Pages: 1 