- #1
Larrytsai
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Homework Statement
Let C be the counter-clockwise planar circle with center at the origin and radius r > 0. Without computing them, determine F for the following vector fields whether the line integrals int(Fdr)
are positive negative or zero
F = xi + yj
F = -yi + xj
F = yi -xj
F= i + j
The Attempt at a Solution
I applies greens theorem
for the first force vector F = xi + yj
so I take the partial of Q wrt x and get 1 and p wrt y and get 1
and i get double zero
but when i do this for 2nd one F = -yi + xj and 3rd one, my answers seem to be opposite of what i got.
F = -yi + xj
partial Q / partial x = -1
partial P/ partial y = 1
so i would get a negative number. but answer is positive.
greens theorem = double integral (-2)dA