Question

What is spherical polar coordinate system?

Answer 1

We can describe any point in 3 dimensional space using a radius `r` and two angles `theta` and `phi` as:

`(r cos theta cos phi, r sin theta cos phi, r sin phi)`

Explanation:

We can describe any point in the X-Y plane as `(r cos theta, r sin theta)`, where `r` is the radius and `theta` is an angle from the `x` axis.

Then rotate into the Z dimension by rotating by angle `phi` about a line in the X-Y plane through the origin perpendicular to the radius.

That results in a point `(r cos theta cos phi, r sin theta cos phi, r sin phi)`

This point lies on the sphere of radius `r`