If the distance of the far point for a myopia pa dent is doubled, the focal length of the lens required to cure it will become:

Question

If the distance of the far point for a myopia pa dent is doubled, the focal length of the lens required to cure it will become: (A) double (B) half (C) the same but a concave lens (D) the same but a convex lens

Tardigrade Admin · Accepted Answer

In the eye defect of myopia, the focal length of lens f=-d, here d is the distance of far point. Therefore, if d is doubled the focal length will also be doubled.

Q. If the distance of the far point for a myopia pa dent is doubled, the focal length of the lens required to cure it will become:

double

half

the same but a concave lens

the same but a convex lens

In the eye defect of myopia, the focal length of lens $f = - d,$ here d is the distance of far point. Therefore, if $d$ is doubled the focal length will also be doubled.

Q. If the distance of the far point for a myopia pa dent is doubled, the focal length of the lens required to cure it will become:

double

half

the same but a concave lens

the same but a convex lens

In the eye defect of myopia, the focal length of lens f=−d, here d is the distance of far point. Therefore, if d is doubled the focal length will also be doubled.

In the eye defect of myopia, the focal length of lens $f = - d,$ here d is the distance of far point. Therefore, if $d$ is doubled the focal length will also be doubled.