# Volume spherical coordinates

1. May 13, 2010

### fishingspree2

Say I have a solid given using polar coordinates
I want to compute its volume.

We know that when switching from cartesian to polar, dV becomes $$\rho^{2}\sin\phi d\rho d\theta d\phi$$

But I am not converting from cartesian to polar, I am already in polar coordinates.

do I still have to carry the $$\rho^{2}\sin\phi$$ that comes from the dV conversion formula?

2. May 13, 2010

### lugita15

Yes, you do. That formula for dV is the volume element in spherical coordinates, whether you're converting into spherical coordinates or staying in spherical coordinates.