Question

What is the focal length of 2.30 D reading glasses found on the rack in a drugstore?

Answer 1

Answer:

Focal length, f = 0.43 meters

Explanation:

It is given that,

Power of the reading glasses, P = 2.3 D

We need to calculate the focal length of the reading glasses. The relationship between the power and the focal length inverse i.e.

$P=\dfrac{1}{f}$

$f=\dfrac{1}{P}$

$f=\dfrac{1}{2.3\ D}$

f = 0.43 m

So, the focal length of the reading glasses found on the rack in a drugstore is 0.43 meters.