Normal ray:-The normal ray in lens is direct pass through the lens and ray is not deviate.Because if normal ray is passing through rare medium to densor medium then ray is direct pass through the one medium to Another medium without any deviation.
In lens if normal ray is passing through the direction of principal axis then ray is not deviated so the principal axis considered as a normal ray.
why ray parallel to principal axis passes through focus
Q.all the rays of light parallel to principal axis after reflection passes through
Ans;-All the rays of light parallel to principal axis after reflection passes through the focus.
Q.A ray parallel to the principal axis is incident at 30.
Q.a ray parallel to the principal axis after reflection will pass through the
Ans:-Focus
a non paraxial rays parallel to the principal axis after reflection
Q.how are the rays parallel to the principal axis reflected by a convex mirror:-
the ray which move away to the principal axis is
a ray parallel to the principal axis passes through
