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प्रश्न
The kind of lens required to correct Myopia
Name the following:
The kind of lens required to correct near sightedness.
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उत्तर
Concave lens
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संबंधित प्रश्न
What is the scientific name of
long-sightedness?
What is short-sightedness? State the two causes of short-sightedness (or myopia). With the help of ray diagrams, show:
(i) the eye-defect short-sightedness.
(ii) correction of short-sightedness by using a lens.
An eye has a far point of 2 m. What type of lens in spectacles would be needed to increase the far point to infinity? Also calculate the power of lens required. Is this eye long-sighted or short-sighted?
The picture given here shows a person wearing 'half-moon' spectacles. What sort of eye-defect do do you think he has? Why are these particular spectacles useful to him?
Name the following:
The eye defect caused due to shortening of the eye ball from front to back.
List two causes of presbyopia. Draw labelled diagram of a lens used for the correction of this defect of vision.
Give Reason:
Older people require glasses to read and write.
The diagram given below represents the cross-section of the human eye:
(i) Name the parts labeled 1—12.
(ii) What is the function of the part marked ‘10’?
(iii) What would happen if part ‘5’ is damaged or cut?
A person needs a lens of power –4.5 D for correction of her vision.
- What kind of defect in vision is she suffering from?
- What is the focal length of the corrective lens?
- What is the nature of the corrective lens?
Observe the figure whether it is correct or not and explain the phenomenon.
