Evaluating a Line integral in spherical polar coordinates

[wam_mi]

Homework Statement

Consider the vector potential
A = cr * [(sin theta)^2 * (cos fi) * (sin fi) + (cos theta)^2 ) er
+ (sin theta) cos (theta) * [(sin fi) (cos fi)  − 1] e theta
+ {(sin theta) (cosfi)^2 } efi


er: in the er direction
e theta: in the e theta direction
e fi: in the e fi direction

A is given in spherical polar coordinates.

Calculate the line integral A dot dl with closed curve C, where C is the circle parametrised by fi, at some arbitrary values of (r, theta)


Please help, I really can't do this line integral.
It would also be nice to see a full solution!


Can anyone please also tell me what's the general trick of tackling problems with line integral?


Many thanks guys!

Homework Equations

The Attempt at a Solution

 

[gabbagabbahey]

Please help, I really can't do this line integral.
It would also be nice to see a full solution!

The Attempt at a Solution

We don't provide full solutions;it's against forum policy!

Make an attempt, post your work and we'll help you through it.

As a hint, a good starting point is to find an expression for dl (after all, you are going to have a heck of a time integrating A.dl if you don't know what dl is! )...