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# Gradient of scalar fields in cylindrical polar coordinates watch

1. (sorry the title is meant to say spherical, not cylindrical)

I notice that there are Theta hats in the del operator for SPHERICAL polar coordinates, as in, the unit vector in the theta direction.

Just so it happens that I'm stuck on a physics question involving electric fields associated with dipoles which at certain points point in the theta hat direction....where does theta hat point to?
2. (Original post by Plutoniummatt)
(sorry the title is meant to say spherical, not cylindrical)

I notice that there are Theta hats in the del operator for SPHERICAL polar coordinates, as in, the unit vector in the theta direction.

Just so it happens that I'm stuck on a physics question involving electric fields associated with dipoles which at certain points point in the theta hat direction....where does theta hat point to?

Cribbed straight from wikipedia:

are the local orthogonal [[unit vectors]] in the directions of increasing , respectively.

Refer to:

http://en.wikipedia.org/wiki/Spheric...rdinate_system for the directions of
3. and the direction of increasing THETA hat is....what? theta is an angle...measured from the Z axis to unit vector r...
4. Hope this helps.

If you fix the other two co-ordinates and increase theta, then the direction that you point moves in will be that of the unit vector theta hat.

If theta is the angle of elevation above the plane. Then drawing a circle through the origin, your point in question, and the zenith, or nadir, then theta hat will be tangential to that circle in the direction the point would move if theta alone was increasing.

Best I do as an explanation.

Edit: slightly better description.
5. aha....thanks

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