The human eye and the colourful world Worksheet-6
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What is the least distance of distinct vision ?
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What kind of lens is there in human eye ?
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Name the screen on which eye forms the image.
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Is cornea transparent to light ?
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What is the range of vision of a normal human eye ?
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Which phenomenon of vision is used in cinematography?
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What type of cells are lacking in a person who is colour blind ?
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Which type of retinal cells respond to brightness of light ?
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Which defect of vision can be rectified using a convex lens ?
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Which defect of vision can be rectified using a concave lens ?
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How is the vision of a person having cataract restored?
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Which defect of the eye can be corrected using a cylindrical lens ?
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Which colour has largest Wavelength ?
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Which colour suffers least deviation on passing through a prism ?
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What phenomenon causes twinkling of stars on a clear night ?'
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Which phenomenon is responsible for increasing the apparent length of the day by 4 minutes ?
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Why do stars appear higher than they actually are ?
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What enables the eye to focus objects at different distances?
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Why does it take some time to see objects in a cinema hall, when we just enter the hall ?
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How is the amount of light entering the eye controlled ?
Answer:
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least distance of distinct vision is 25 cm.
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double convex lens.
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Retina of the eye.
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Yes.
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From 25 cm to infinity.
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Property of persistence of vision.
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Cone shaped cells
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The rod shaped cells
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Hypermetropia or long sightedness.
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Myopia or short sightedness.
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By cataract surgery.
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Astigmatism.
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Red
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Red
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atmospheric refraction.
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Atmospheric refraction.
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Atmospheric refraction from upper rarer layers to lower denser layers.
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Change in focal length of eye lens by the action of ciliary muscles holding the eye lens.
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Pupil of the eyes take some time to expand and allow more light to enter the eye.
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The iris regulates the amount of light entering the eye by adjusting the size of the pupil of the eye.