| 1. | Twinkling of stars is due to atmospheric ? | |
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internal reflection of light by clouds.
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scattering of light by dust particles
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refraction of light by different layers of varying refractive indices
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dispersion of light by water droplets
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Report Question| 2. | The bluish colour of water in deep sea is due to ? | |
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absorption of light by the sea
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reflection of sky in water
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the presence of algae and other plants found in water
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scattering of light
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| 3. | The focal length of the eye lens increases when eye muscles ? | |
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contract and lens becomes thinner
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are relaxed and lens becomes thinner
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are relaxed and lens becomes thicker
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contract and lens becomes thicker
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| 4. | The clear sky appears blue because ? | |
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light of all other colours is scattered more than the violet and blue colour lights by the atmosphere.
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ultraviolet radiations are absorbed in the atmosphere.
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violet and blue lights get scattered more than lights of all other colours by the atmosphere.
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blue light gets absorbed in the atmosphere.
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| 5. | A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power ? | |
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– 0.5 D
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– 0.2 D
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+ 0.5 D
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+ 0.2 D
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| 6. | At noon the sun appears white as ? | |
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red colour is scattered the most
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blue colour is scattered the most
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light is least scattered
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all the colours of the white light are scattered away
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| 7. | The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light ? | |
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is scattered the least by smoke or fog
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moves fastest in air
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is absorbed the most by smoke or fog
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is scattered the most by smoke or fog
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| 8. | When light rays enter the eye, most of the refraction occurs at the ? | |
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pupil
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crystalline lens
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outer surface of the cornea
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iris
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| 9. | At noon, the Sun appears white as ? | |
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all the colours of the white light are scattered away
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light is least scattered
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red colour is scattered the most
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blue colour is scattered the most
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| 10. | Cornea is a transparent spherical structure which ____ ? | |
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Scatters light
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Reflects light
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Refracts light
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None
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