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प्रश्न
Which defect of vision can be rectified:
by using a convex lens?
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उत्तर
Hypermetropia can be rectified by using convex lenses.
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संबंधित प्रश्न
Name the defect of vision in a person:
whose near point is more than 25 on away.
Which defect of vision can be rectified:
by using a concave lens?
Name any two defects of vision which can be corrected by using spectacles.
Where is the near point of a person suffering from hypermetropia (or long-sightedness)?
Differentiate between myopia and hypermetropia.
What is long-sightedness? State the two causes of long-sightedness (or hypermetropia). With the help of ray diagrams, show:
(i) the eye-defect long-sightedness.
(ii) correction of long-sightedness by using a lens.
The defect of vision in which the eye-lens of a person gets progressively cloudy resulting in blurred vision is called:
(a) myopia
(b) presbyopia
(c) colourblindness
(d) cataract
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 an old man
- if the person is a young man
Which part of the eye is grafted in a needy patient from a donated eye?
What is meant by optical illusion? Give one example.
An old man cannot see objects closer than 1 m from the eye clearly. Name the defect of vision he is suffering from. How can it be corrected? Draw ray diagram for the (i) defect of vision and also (ii) for its correction.
Choose the odd one out from the following terms and name the category to which the others belong.
Endolymph, Tympanic membrane, Semi-circular canal, Blind spot
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?
A person is unable to see objects distinctly placed within 50 cm from his eyes.
(a) Name the defect of vision the person is suffering from and list its two possible causes.
(b) Draw a ray diagram to show the defect in the above case.
(c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm.
(d) Draw a labeled diagram for the correction of the defect in the above case.
Give Reason:
Older people require glasses to read and write.
Study the following diagram carefully and then answer the questions that follow. The diagram is depicting a defect of the human eye :
(i) Identify the defect shown in the diagram.
(ii) Give two possible reasons for the above defect.
What are the causes of ‘Myopia’?
Which of the following statement is correct?
Draw ray diagram showing myopic eye.
