Dear student,
You are asking if the focal length of a lens is 20 cm, what is its power in diopters?
Calculating Lens Power:
Formula:
Given:
Calculation:
Therefore, the power of the lens is +5 diopters
Why is it positive?
convex lens
Additional Notes:
Therefore, if a lens has a focal length of 20 cm, its power is +5 diopters. This means it is a convex lens capable of converging light rays.