The near point of a hypermetropic eye is `50 cm`. Calculate the power of the lens to enable him to read a book at `40 cm` ?

The far point of a myopic eye is at 50 cm . Calculate the power of the lens to correct his vision.

The near point of hypermetropic eye is 40 cm . What is the power of the lens used to correct this defect ?

The near point of a hypermetropic person is 50 cm from the eye. What is the power of the lens required to enable him to read clearly a book held at 25 cm from the eye ?

The near point of a hypermetropic person is 50 cm from the eye. What is the power of the lens required to enable him to read clearly a book held at 25 cm from the eye ?

The far point of a myopia person is 200 cm. Calculate the power of a lens required to enable him to see distant objects clearly.

(a) The near point of a hypermetropic person is at 75 cm from the eye. What is the power of the lens required to enable him to read clearly a book held at 25 cm from the eye ? (b) In what way does the corrective lens help the person above ? Does the lens magnify objects held near the eye ? ( c) The person above prefers to remove his spectacles while looking at the sky. Explain why ?