Question

A thin lens has focal length – 20 cm. What is the power of the lens and what is its focal length?​

Answer 1

Answer:

Power of lens is P=

f

1

,focal length should be in meter

f=−25cm=−.25m

so P=

−0.25

1

=−4D

Since the focal length is negative, it is a concave lens or diverging lens.

Answer 2

Answer:

Power of lens is P=

f

1

,focal length should be in meter

f=−25cm=−.25m

so P=

−0.25

1

=−4D

Since the focal length is negative, it is a concave lens or diverging lens

hope it helps plzz mark brainliest