hi,

i have a question in stokes theorem, and i am having trouble finding the

normal vector.

we have a curve

and our goal is to calculate the work done by the field

along the curve.

so i use stokes theorem, and pick a surface S enclosed by C:

and the normal vector N, will be in the (-j) direction.

eventually what i get is using stokes theorem:

How do i find the length and direction of the normal vector n?

thanks in advance