Solution to Peculiar Problem: Can Closed Integral be Evaluated?

  • Thread starter Thread starter Kolahal Bhattacharya
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The discussion revolves around evaluating the closed integral of the form closed integral{F dS}, where F is a vector and dS is treated as a scalar. The original poster expresses uncertainty about the evaluation method, suggesting that F may need a specific relationship with the normal vector n. They clarify that there is no cross product involved and reflect on a misreading of a related exam question. A potential observation is made regarding the relationship between F, dS, and n, hinting at the use of triple product rules. The poster concludes by acknowledging difficulty in conceptualizing dS as a vector independent of n.
Kolahal Bhattacharya
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Homework Statement



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. Homework Equations



The Attempt at a Solution



I do not want to evaluate this.I just want to know if it is done.And how?
 
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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?
 
OK,there is no cross product.This actually appeared in the exam I appeared yesterday.
 
I'll think about this, but let me know what the answer is when you find out.
 
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).
 
Hmm. Ok. I'll keep thinking about it. But I'm having trouble thinking about dS as a vector separate from n.
 
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