Question

The focal length of
a lens with power 2.5D is fill in the blanks​

Answer 1

Answer:

Concave lens with a focal length of 40 cm

Explanation:

P=

f(inmeter)

1

f=

P

1

=

2.5

1

=

−25

1

⇒f=

25

−1000

cm=−40cm

Focal length (f) of a concave lens is always negative.