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Easy

Question

# A person is suffering from myopic defect. He is able to see clear objects placed at 15 *cm*. What type and of what focal length of lens he should use to see clearly the object placed 60 *cm* away

- Concave lens of 20
*cm* focal length
- Convex lens of 20
*cm* focal length
- Concave lens of 12
*cm* focal length
- Convex lens of 12
*cm* focal length

*cm*focal length*cm*focal length*cm*focal length*cm*focal length## The correct answer is: Concave lens of 20 *cm* focal length

### For viewing far objects, concave lenses are used and for concave lens

*u* = wants to see ; *v* = can see

so from .

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