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प्रश्न
The day is longer on the earth by about 4 minutes because:
(a) the earth is round in shape
(b) the earth rotates on its axis
(c) the earth revolves around the sun
(d) the earth has atmosphere
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उत्तर
the earth has atmosphere
The day is longer by about four minutes because the earth has an atmosphere.
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संबंधित प्रश्न
What is atmospheric refraction? Use this phenomenon to explain the following natural events:
Twinkling of stars
Draw diagrams to illustrate your answers.
Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is:
sunrise advanced?
Why do stars seem higher than they actually are? Illustrate your answer with the help of a diagram.
The twinkling of stars is due to atmospheric:
(a) reflection of light
(b) dispersion of light
(c) interference of light
(d) refraction of light
The atmospheric refraction of light causes the twinkling of:
(a) planets only
(b) stars only
(c) planets and stars
(d) stars and satellites
The stars appear higher in the sky than they actually are, due to:
(a) diffraction of light
(b) scattering of light
(c) refraction of light
(d) reflection of light
The stars twinkle but the planets do not twinkle at night because:
(a) the stars are small but the planets are large
(b) the stars are very large but planets are small
(c) the stars are much nearer but planets are far off
(d) the stars are far off but planets are nearer to earth
As light from a far off star comes down towards the earth:
(a) it bends away from the normal
(b) it bends towards the normal
(c) it does not bend at all
(d) it is reflected back
We know that light refracts (or bends) when it goes from one medium to another. Now, the atmosphere contains only air. Then how does light get refracted on passing through only air in the atmosphere?
A student claims that because of atmospheric refraction, the sun can be seen after it has set, and the day is, therefore, longer than if the earth had no atmosphere.
- What does the student mean by saying that the sun can be seen after it has set?
- Do you think that the students’ conclusion is correct?
A student claims that because of atmospheric refraction, the sun can be seen after it has set, and the day is, therefore, longer than if the earth had no atmosphere.
Do you think that the students conclusion is correct?
Why does the sky appear blue on a clear day?
What causes the scattering of blue component of sunlight in the atmosphere?
A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
Explain the refraction of light through a triangular glass prism using a labelled ray diagram. Hence define the angle of deviation.
