Using my understanding of calculus, I don't understand why line integrals in 3-d space(adsbygoogle = window.adsbygoogle || []).push({});

can give a result > 0. You are following a line and integrating under that line. The line

has some length. But according to my understanding of calculus, it does not have a width.

What is this arbitrary width, and where does it come from?

Thank you

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# Line integral: how can it be > 0?

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