Normal to a Sphere

Normal to a Sphere

The normal to a sphere at point $$p$$ passes through the centre of the sphere.

For centre $$C(a,b,c)$$ and point $$P(x_1,y_1,z_1)$$, its direction vector is:

$$(x_1-a)\hat i+(y_1-b)\hat j+(z_1-c)\hat k$$

Usage

- Used to obtain the normal line at a point on a sphere.