Question

The focal length of a concave lens with power - 4 D is
(A) - 0.5 m
(B) 0.5 m
(C) -0.25 m
(D) 0.25 m​

Answer 1

Answer:

-0.25 m

Explanation:

P=1/f

f=1/p

=-1/4

f= -o.25 m