Find the distance on focal plane where parallel and paraxial rays meet after reflection
Answers
Answer:
this is ur answer
Explanation:
Large spherical mirror from figure (b) we can be that in care of large spherical mirror the mirror does not have a well defined focal point this is called spherical observed and results in a blurned image of an extended object.
From figure (c) we can see that a spherical mirror that is small compared to is radius of curvature the mirror approximation of parabolic mirror.
So rays that arrive parallel to the optical axis are reflection to a well defined focal point so we can say for paraxial rays spherical mirror has are defined focus well
Hence in figure we can see that a signal rays is reflected by a spherical concave mirror.the incident ray is parallel to optical axis .For paraxial rays all rays will meet at the focus.
R=CF+FP
and angle of incidence =angle of reflection
sinθ≃θ (small angle approximates)
FX≃FP or CF≃FP
R=CF+FP
FP+FP
2FP
2×F
f=
2
R
(in the small angles approximation for paraxial approximation ) focal length of a mirror is half times its Radius. hope it helps