﻿ A person with defective eyesight is unable to see objects clearly nearer than 1.5 m. He wants to read a book placed at a distance of 30 cm from his eyes. Find the power of the lens he requires for his spectacles.    : Kaysons Education

# A Person With Defective Eyesight Is Unable To See Objects Clearly Nearer Than 1.5 M. He Wants To Read A Book Placed At A Distance Of 30 Cm From His Eyes. Find The Power Of The Lens He Requires For His Spectacles.

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## Question

### Solution

Correct option is

+ 2.67 D

The person is hypermetropic. This defect is correct by using a convex lens. Putting u = –30 cm and v = 1.5 m = –150 cm in the lens formula gives f = +37.5. Therefore, the lower of the lens = +2.67 D.

#### SIMILAR QUESTIONS

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Q9

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