Question

The far point of an eye is 180 cm. A corrective lens is to be used to allow this eye to focus clearly on objects a great distance away. What should be the focal length of this lens

Answer 1

The focal length of this lens is f = 0.55 D

Step-by-step explanation:

Given that the far point of an eye ( d )= 180 cm = 1.8 m

We know that focal length of lens is given by

`f = (1)/(d)`

Put the value of d in above equation we get

`f = (1)/(1.8) \ m^(-1)`

f = 0.55 D

Therefore the focal length of this lens is f = 0.55 D