# Spherical Coordinate System with Unit Vectors

Spherical Coordinate System with Unit Vectors

This Demonstration shows a vector in the spherical coordinate system with coordinates , where is the length of , is the angle in the - plane from the axis to the projection of onto the - plane, and is the angle between the axis and . Also shown is a unit vector that is normal to the sphere (of radius centered at the origin) at the red point and two unit vectors and that determine the tangent plane to the sphere at the red point.

r

(r,θ,ϕ)

r

r

θ

x

y

x

r

x

y

ϕ

z

r

n

r

t

1

t

2