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A person can see clearly objects only wh...

A person can see clearly objects only when they lie between 50 cm and 400 cm from his eyes. In order to increase the maximum distance of distinct vision to infinity, the type and power of the correcting lens, the person has to use, will be

A

convex, + 0.15 dioptre

B

convex , + 2.25 dioptre

C

concave, -0.25 dioptre

D

concave, - 0.2 dioptre.

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TARGET PUBLICATION-OPTICS-EXERCISE
  1. A converging beam of rays is incident on a diverging lens. Having pass...

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  2. An object is located 4 m from the first of two thin converging lenses ...

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  3. A person can see clearly objects only when they lie between 50 cm and ...

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  4. Two convex lenses of focal lengths f(1)andf(2) form images with magnif...

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  5. The equiconvex lens has focal length f. If is cut perpendicular to the...

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  6. A plano-convex lens is made of material having refractive index 1.5. T...

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  7. A convex lens (with material of refractive index of 3/2) has two surfa...

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  8. A double convex lens has focal length 25 cm. The radius of curvature o...

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  9. The power of a biconvex lens is 10 dioptre and the radius of curvature...

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  10. A convex lens of glass (mu=1.5) has a focal length of 8 cm when placed...

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  11. A convex lens of glass (mu(g)=1.45) has focal length f(g) is air. The ...

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  12. A thin convex lens made from crown glass (mu=(3)/(2)) has focal f. Whe...

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  13. Two similar thin equiconvex lenses, of focal length f each, are kept c...

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  14. Two identical thin plano-convex glass lenses (refractive index 1.5) ea...

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  15. A plnao=convex lens fits exactly into a plano-concave lens. Their plan...

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  16. A plano-convex lens fits exactly into plano-concave lens as shown in t...

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  17. A comvex lens and a concave lens are placed in contact. The ratio of m...

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  18. Two identical glass (mu(w)=3//2) equiconvex lenses of focal length f e...

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  19. Two identical equiconvex lenses, each of focal length 'f' are placed s...

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  20. A bi-convex lens is formed with two thin plano convex lenses as shown ...

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