Question

Question #b01f4

Answer 1

Power of a lens is defined as the ability to converge or diverge light ray.
So, Higher the focal length lower the power.
Mathematically it is defined as `P=100/f` where f is given in cm
P=100/5=20 dp

Answer 2

`"20 diopter"`

Explanation:

Power = `1/"Focal length" = 1/(5 cancel"cm" × 10^-2 "m"/cancel"cm") = "20 diopter"`