Q22 of 36 Page 283

A concave lens has a focal length of 50 cm Calculate its power.

Given,

Focal length of concave lens = -50 cm


= m


= -0.50 m


To find: Power of lens?


We know,




Power of lens = - 2 Dioptres.


Since the focal length of a concave lens is always negative so power of the concave lens is -2 diopters.


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