A person with a myopia eye cannot see objects beyond a distance of 1.5 m. What would be the power of the corrective lens used to restore proper vision ?

Explanation

The corrective lens should make the objects at infinity appear at the far point.
`:.` For object at infinity, object distance `= u = -oo`.
For the myopic eye, far-point distance, v = -1.5 m.
By lens formula
`(1)/(f) = (1)/(u) - (1)/(v) = (1)/(-1.5) - (1)/(-oo) = (1)/(-1.5) + 0 = (1)/(-1.5)`
f = -1.5 m.
Power , `P = (1)/("f(in m)") = (1)/(1.50) = -0.67 D`
Negative sign shows that the corrective lens is a concave.