Question

Focal length of a convex lens is 25cm.its power would be

Answer 1

Answer:

0.4 D

Explanation:

Focal length (f)=25 cm

                       = 25/10

                       = 2.5 m

Now,

Power= 1/f

          = 1/2.5  

           =0.4 Diopter

Answer 2

-4.0 D is the answers....