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What is the power of a lens that can be ...

What is the power of a lens that can be used to correct the eye defect of a person who cannot see the objects distinctly kept beyond 2 m ?

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Verified by Experts

`-0.5D`
(`because` For a myopic eye the focal length of the corrective lens is equal to the far point of the myopic person, i.e., f = -2 m).
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KUMAR PRAKASHAN-THE HUMAN EYE AND THE COLOURFUL WORLD-OBJECTIVE QUESTIONS AND ANSWERS (Answer the following questions in very short as directed (Miscellaneous) )
  1. What is the power of a lens that can be used to correct the eye defect...

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  2. Why does the Sun appear white at noon ?

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  3. Why is the eye lens not perfectly solid ?

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  4. What is the focal length of plain goggles ?

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  5. What happens when elasticity of the crystalline lens is reduced to zer...

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  6. Which defect of the eye occurs due to distortion of cornea ?

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  7. How the defect of astigmatism can be corrected ?

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  8. What is colour blindness? How can it be cured?

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  9. In hypermetropia, how does the size of eyeball change ?

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  10. What change occurs in the focal length, when our eye lens becomes thic...

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  11. What are rods and cones ?

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  12. What is cataract ?

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  13. What would have been the colour of the sky, had there been no atmosphe...

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  14. Due to which phenomenon is the colour of water in deep sea blue ?

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  15. What is the cause for presbyopia ?

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  16. Give the relationship between wavelength of light and its angle of dev...

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  17. For which colour has the glass larger refractive index – violet or gre...

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  18. Which part of human eye is also known as 'white of the eye' ?

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  19. Why is blind spot so called ?

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  20. Which liquid is filled in the space between the eye lens and the retin...

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