Q. Define Pole, the Centre of Curvature, the Radius of Curvature, Principal Axis, Aperture, Focus, and Focal Length of a Spherical Mirror
Answer: Mirrors form a special part of physics as it is an interesting subject that explains a lot about light and its reflections. The spherical mirror can either be concave or convex. A pole of the said spherical mirror is its center. It is located on the surface of the spherical mirror. The Centre of Curvature refers to the curvature of the spherical mirror. The radius of curvature refers to the point of apparent intersection of the parallel rays that are perpendicular to their principal axis in the reflection. It is also defined as the distance between the Principal Focus and the Pole of a mirror. The principal axis is the imaginary line that goes through the center of curvature and the pole. Aperture is used to determine the size of the spherical mirror and is defined as the diameter of the reflecting surface. The focus is a point on the surface of the spherical mirror which seems to be the origin of the parallel light rays perpendicular to the Principal Axis passing or arising out after the reflection. It is a point on the Principal Axis. The distance between the center of an object appearing on the mirror and the pole is known as the Focal Length.