- #1

NicolaiTheDane

- 100

- 10

As I understand it, it is suppose to tell me, what the "curl" around a boundary is. However there are several examples I can find, where this doesn't make sense. My understanding of curl, is that it is expression of rather there is a tendency for turn or not (vague, hopefully good enough). So a field like $$v = (y^2)*i$$ would have curl, because the further away you get from y = 0, the higher strength the field has.

Now the part that doesn't make sense to me, is when asked to compute the curl around a triangle, with the points (0,0), (0,4), and (0,2), it seems intuitive to me, that the flat line, along the y axis, would provide some, if not most of the curl to the triangle, as the vector field would push more on the outer end of the line, then on the inner end. However when I calculate it, it seems that the one side that to me would provide no curl, provides most of it (the one running along the x axis), while the one along the y axis, provides 0 curl.

This suggest to me, that there is something I simply do not understand. Also I do not understand, why curl around a closed curve, is always zero. To me that seems to suggest curl around a volume is impossible.

I guess what I am asking, if I were to boil it down, is just what is curl. What am I calculating with Greens and Stokes theorem, because it cannot possible be what I think it is.

Thanks in advance