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Question 2:
A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision?
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Question 3:
What is the far point and near point of the human eye with normal vision?
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Question 4:
A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?
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Question 5:
A person needs a lens of power −5.5 dioptres for correcting his distant vision. For correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required for correcting (i) distant vision, and (ii) near vision?
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Question 6:
The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem?
age No 198:
Question 7:
Make a diagram to show how hypermetropia is corrected. The near point of a hypermetropic eye is 1 m. What is the power of the lens required to correct this defect? Assume that the near point of the normal eye is 25 cm.
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Question 8:
Why is a normal eye not able to see clearly the objects placed closer than 25 cm?
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Question 9:
What happens to the image distance in the eye when we increase the distance of an object from the eye?