Question

A convex lens of focal length 25 cm is kept in contact with a concave lens of focal length 30 cm, so the focal length of the combination of lenses will be;

(A) 45 cm
(B) 100 cm
(C) 150cm
(D) 90cm

Answer 1

45 is the answer of the above question

Answer 2

focal length of both the lenses will be 45cm.