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प्रश्न
Which of the following is not caused by the atmospheric refraction of light?
(a) twinkling of stars at night
(b) sun appearing higher in the sky than it actually is
(c) sun becoming visible two minutes before actual sunrise
(d) sun appearing red at sunset
उत्तर
sun appearing red at sunset
The sun appears red at sunset not because of the atmospheric refraction of light but because of the scattering effect of light.
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संबंधित प्रश्न
What is atmospheric refraction? Use this phenomenon to explain the following natural events:
Advanced sun-rise and delayed sun-set.
Draw diagrams to illustrate your answers.
The phenomenon that causes the twinkling of stars is refraction of light.
Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is:
sunrise advanced?
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
Due to atmospheric refraction of sunlight, the time from sunrise to sunset is lengthened by about:
(a) 6 minutes
(b) 2 minutes
(c) 4 minutes
(d) 5 minutes
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
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?
State two effects produced by the scattering of light by the atmosphere.
A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
Refraction of light by the earth’s atmosphere due to variation in air density is called ____________.