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You are not logged in. #1 20060430 18:11:35
Surface Integral Question
#2 20060501 01:33:14
Re: Surface Integral QuestionWhat you are doing is integrating over the surfaces of a block. So you can set up 6 different integrals, each with respect to two variables, and add them all together. Last edited by Ricky (20060501 01:34:07) "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #5 20060506 17:57:03
Re: Surface Integral QuestionActually my lecturer told me to use a flux integral F.ndS. He talked about normal to the surface and something like that, eg the right most surface of the box has a positive j component. In that case I'd use dx and dz he says. But I still don't really understand this concept. (by the way I can't ask him too much because this is an assignment question). Last edited by renjer (20060506 17:57:50) #7 20060508 00:08:55
Re: Surface Integral QuestionSorry about the delay. If you have trouble understanding any of this, let me know. It's hard to do a complete explanation because there are a lot of things you probably understand, and I don't want to write a book if I don't have to . Ok, so we have a cube with six sides: Now we have the normals. I'm going to assume we want outward facing normals, although I'm not entirely sure why that fact isn't given to you. Finally, let: So now: Then we have: Not quite sure why latex doesn't format that right, but at least it's readable. After integrating all of these, I get 760. Is that what you get doing the divergence thm? "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #8 20060508 00:50:01
Re: Surface Integral QuestionYes of course, using the divergence theorem is so much faster and easier too. Last edited by renjer (20060508 01:30:28) 