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प्रश्न
State one role of ciliary muscles in the human eye.
उत्तर
The ciliary muscles in the eye support the lens and hold it in place. They also change the shape of lens by contracting or relaxing. This process is called accommodation.
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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.
Explain two possible reasons of myopia. How can it be corrected? Explain with a suitable diagram.
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.
A person having short-sight cannot see objects clearly beyond a distance of 1.5 m. What would be the nature and power of the corrective lens to restore proper vision?
To read a book held at a distance of 25 cm, will she need converging or diverging spectacle lenses?
A student cannot see a chart hanging on a wall placed at a distance of 3 m from him. Name the defect of vision he is suffering from. How can it be corrected? Draw ray diagrams for the (i) defect of vision and also (ii) for its correction.
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.
Give Technical Term:
The type of lens used to correct myopia is
What type of lens is used to correct Astigmatism?
Nearsightedness: elongated eyeball : : farsightedness: _______
