Question

Surface elements in spherical polar coordinate system

Answer 1

Spherical coordinates (r, θ, φ) as commonly used in physics (ISO convention): radialdistance r, polar angle θ (theta), and azimuthal angle φ (phi). ...Spherical coordinates (r, θ, φ) as often used in mathematics: radial distance r, azimuthal angle θ, and polar angle φ.