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#1 2015-05-09 00:26:12

Mathn00b
Guest

Flux integral confusion

Hello,

I've got a problem with solving a flux integral. I've got confused. Is it the way I started correct? Should it be calculated using polar coordinates over drdThetadz or dxdydz?
Please find the problem and the workings attached!

flux%20integral%20problem%20and%20workings_zpsr4lanoj5.jpg


Thank you!

#2 2015-05-09 00:50:59

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
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Re: Flux integral confusion

I am new to vector calculus too but how about we compute the divergence first? And apply Thedivergence theorem?

Last edited by Agnishom (2015-05-09 00:53:04)


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#3 2015-05-09 11:53:29

Mathn00b
Member
Registered: 2015-05-09
Posts: 1

Re: Flux integral confusion

, which in my case will give
, which will give just
Dunno if it is correct
Also found another approach but there I got quite unpleasant integral.

This surface is the graph of the function

, so use the graph parametrization

We shall use the following (very important!) general formula for the upward normal of a surface defined by an equation of the form


   

For the surface of interest here, it follows that:

And we have

So

So we have   

Last edited by Mathn00b (2015-05-10 03:23:43)

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