Question

Far point of a person is 5 m. What is the lens he should use to correct his defect?
What is it's focal length ?​

Answer 1

Answer:

the person can see clearly the object up to 5 m then u = - ∞

and v = - 5 m

then after applying the lens formula focal length comes to be 5 m then after applying the power formula p = -1/f

power will be -0.5 D

it implies that the person have to use concave lens and he is suffering from  myopia that means his eyeballs elongated.

hope this help mate