Which type of mirror has :
(a) positive focal length ?
(ii) negative focal length ?

If a mirror has a focal length of + 15 cm, it is a

Aravind requires a concave mirror of focal length 10 cm for an experiment of light. He is having lot of concave mirrors in his lab without its focal length values. To determine the focal length of mirror in his laboratory, what are the apparatus required ? How focal length can be determined ?

Which of the following will be a more efficient solar furnace ? (i) concave mirror of parabolic shape of short focal length, (ii) concave mirror of long focal length

Define the focal length of mirror

Define focal length of concave mirror.

The focal length of a............ lens is negative.