Q30 of 284 Page 262

Two lenses A and B have power of (i) + 2 D and (ii) - 4 D respectively. What is the nature and f length of each lens ?

Power of lens A = +2D

Power of lens B = -4 D


Lens A is convex; f =+50 cm; Lens B is concave ; f =- 25 cm


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