- #1

- 1,868

- 0

## Homework Statement

Hi

I am looking at a circle in a Cartesian coordinate system [itex](x, y, z)[/itex], with center at the point [itex](0, 0, L)[/itex] and radius R (so the

*z*-axis is normal to the surface of the circle). From the origin (0, 0, 0), I would like to integrate across the circular surface, i.e.

[tex]

\int_{0}^{\arctan(R/z_0)}{d\theta}\int_{0}^{2\pi}{d\phi}

[/tex]

If I instead of integrating from a point at the origin now integrate from a circle with radius R'<R (also normal to the

*z*-axis), how would the above integrals be generalized?