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प्रश्न
Have a look at the posture of this woman who is reading a book and answer the questions which follow:

What kind of looking glasses she needs?
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उत्तर
Looking glasses with the concave lens are required here.
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.
Name the defect of vision in a person:
whose near point is more than 25 on away.
Your friend can read a book perfectly well but cannot read the writing on blackboard unless she sits on the front row in class.
Is she short-sighted or long-sighted?
A man can read the number of a distant but clearly but he finds difficulty in reading a book.
What type of spectacle lens should he use to correct the defect?
A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:
if the person is a young man
Select the odd one in the following series:
Endolymph, Tympanic membrane, Semi-circular canal, Blind spot.
The diagram alongside represents a section of a mammalian eye.
(i) Label the parts 1 to 5 of the diagram.
(ii) State the function of the parts labelled 4 and 5.
(iii) With the help of a diagram show the short sightedness.

Rewrite the following table so as to match second and third column with first column.
|
Column I
|
Column II
|
Column III
|
|
(i) Myopia
|
Old age problem
|
Bifocal lens
|
|
(ii) Presbyopia
|
Nearsightedness
|
Concave lens.
|
Given below is a diagram showing a defect of vision. Name the defect of vision and draw an accurately labelled diagram to correct this defect.

Assertion: Concave mirrors are used as reflectors in torches, vehicle head lights and in search lights.
Reason: When an object is placed beyond the center of curvature of a concave mirror, the image formed is real and inverted.
