Final answer:
A -4.00 D lens will over-correct the vision of a boy with a far point of 500 cm, as the correct lens power should be -0.20 D. Hence, a -4.00 D lens will not adjust his far point to infinity.
Step-by-step explanation:
A boy with a near point of 50 cm and a far point of 500 cm is considered to be myopic since his far point is less than infinity. Using a lens with a power of -4.00 D to correct his vision to a far point of infinity, we must determine if that lens strength is appropriate.
The formula for the power of a lens in diopters (D) is P = 1/f, where P is the power in diopters and f is the focal length in meters. To correct a myopic eye to a far point of infinity, the focal length of the corrective lens should be the same as the myopic eye's far point, but with a negative sign since the lens is diverging.
Converting the boy's far point from 500 cm to meters gives us 5 meters. Using the formula, the power of the lens needed to correct his vision would be P = 1/5 = 0.20 D. Since -4.00 D is significantly stronger than -0.20 D, a -4.00 D lens would over-correct his vision.
Therefore, the answer is b. False. A -4.00 D lens will not correctly adjust the boy's far point to infinity; it is too strong for this particular correction.