Define (a) centre of curvature (b) radius of curvature ( c) pole (d) peincipal axis, and ( e) aperture, of a spherical mirror with the help of a blabelled diagram.

With reference to spherical lenses, state the meaning of the following terms or define the following terms and draw the diagrams to illustrate the same : (1) centre of curvature (C) (2) radii of curvature (R_(1),R_(2)) (3) principal axis (4) optical centre (O) (5) principal focus (F) (6) focal length (f)

If R is the radius of curvature of a spherical mirror and f is its length, then :

The focal length of a spherical mirror of radius of curvature 30 cm is: