Uses of CONCAVE and CONVEX LENSES

Which of the following statement is correct?

1. Concave lenses are used to correct the defect of vision called hypermetropia
2. Convex are used as magnifying lenses
3. Concave lenses are used in wide angle spy hole in doors
4. Convex are used to correct the defect of vision called myopia

1.ii and iii are correct

2.i and iv are correct

3.ii and iii are wrong

4.ii and iii are correct

EXPLANATION

 

(i) Concave lenses are used to correct the defect of vision called hypermetropia

❌ Incorrect

• Hypermetropia (farsightedness) is corrected using convex lenses, not concave.

• Concave lenses are used for myopia (nearsightedness).

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(ii) Convex lenses are used as magnifying lenses

✅ Correct

• Convex lenses converge light rays and are commonly used in magnifying glasses, microscopes, etc.

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(iii) Concave lenses are used in wide-angle spy holes in doors

✅ Correct

• Concave lenses diverge light rays, giving a wider field of view, which makes them suitable for spy holes/peepholes in doors.

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(iv) Convex lenses are used to correct the defect of vision called myopia

❌ Incorrect

• Myopia is corrected using concave lenses, not convex.

• Convex lenses are for hypermetropia.

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✅ Correct statements:

• (ii) ✔️

• (iii) ✔️

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Final Answer:

✅ Option 1: ii and iii are correct