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Some Topics of Physics

6. Spherical Mirrors : It is part of hollow glass sphere whose one surface is polished.
There are two types of spherical mirror.
(i) Concave Mirror : It is a spherical mirror whose outer surface is polished and inner or concave side is reflecting surface.
(ii) Convex Mirror : It is a spherical mirror whose inner is polished and outer side or convex side is the reflecting surface.
Principal Focus :
A point on the principal axis of a spherical mirror where the rays of light parallel to the principal axis meet or appear to meet after reflection from the mirror.
Focal Length :
The distance between the pole (P) and principal focus(F) of a spherical mirror is called the focal length of the mirror. It is denoted by f.
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