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प्रश्न
Name the defect of vision in which the eye-lens loses its power of accommodation due to old age.
उत्तर
Presbyopia is the defect of vision because of which the eye lens loses its power of accommodation because of old age.
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संबंधित प्रश्न
Given below is a diagram showing a defect of human eye. Study it and answer the following questions.
(i) Name the defect shown in the figure.
(ii) Give reason for this defect of eye in human being.
(iii) Name the type of lens used to correct the eye defect.
A student suffering from myopia is not able to see distinctly the objects placed beyond 5 m. List two possible reasons due to which this defect of vision may have arisen. With the help of ray diagrams, explain
(i) why the student is unable to see distinctly the objects placed beyond 5 m from his eyes.
(ii) the type of the corrective lens used to restore proper vision and how this defect is corrected by the use of this lens.
(b) If, in this case, the numerical value of the focal length of the corrective lens is 5 m, find the power of the lens as per the new Cartesian sign convention
Explain with the help of labelled ray diagram, the defect of vision called myopia and how it is corrected by a lens.
State one role of ciliary muscles in the human eye.
Name the following:
The photosensitive pigment present in the rod cells of the retina.
Write whether the following is true or false:
A convex lens is used for correcting myopia.
Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:
Give two possible reasons for this defect of the eye in human beings.
Name the common defects of the eye.
Give Reason:
When you enter into a dark room from bright because of sunlight, you can not see things for a few seconds.
Which of the following statement is correct?
