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Kolahal Bhattacharya
Mar12-07, 12:08 PM
1. The problem statement, all variables and given/known data

Can anyone say if this can at all be evaluated?
closed integral{F dS} using divrgence theorem/any of its corollary?
here F is a vector and dS is a scalar and there is no dot sign between them.

2. Relevant equations


3. The attempt at a solution

I do not want to evaluate this.I just want to know if it is done.And how?

Dick
Mar12-07, 12:20 PM
I don't think so, unless F has some special relation with the normal vector n. Is it a cross product with n, as in a problem you posted before?

Kolahal Bhattacharya
Mar12-07, 11:36 PM
OK,there is no cross product.This actually appeared in the exam I appeared yesterday.

Dick
Mar13-07, 08:08 AM
I'll think about this, but let me know what the answer is when you find out.

Kolahal Bhattacharya
Mar13-07, 11:44 AM
I misread the question and worked as int{F.dS}...it's easy.
This observation may yield something-
Note that FdS=F(n dot dS).Using triple product rules, we have nx(FxdS)=F(n dot dS)-dS(n dot F) => FdS=F(n dot dS)=nx(FxdS)+dS(n dot F).

Dick
Mar13-07, 12:07 PM
Hmm. Ok. I'll keep thinking about it. But I'm having trouble thinking about dS as a vector separate from n.