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प्रश्न
Why do stars seem higher than they actually are? Illustrate your answer with the help of a diagram.
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उत्तर
Stars seem higher than they actually are because of the phenomenon of atmospheric refraction. This can be understood with the help of given diagram. When the light from a star descends to the earth's surface, it passes through the different layers of the atmosphere. The atmospheric air at higher levels is rarer and the air near the earth's surface is denser, and the light from the star bends more sharply when it passes through the denser layer of air.
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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.
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.
Explain why the planets do not twinkle.
Name two effects produced by the atmospheric refraction.
State whether the following statement is true or false:
The planets twinkle at night due to atmospheric refraction of light.
Fill in the following blank with suitable word:
We can see the sun about ................ minutes before the actual sunrise and about ................ minutes after the actual sunset because of atmospheric ................
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
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
By how much time the day would have been shorter if the earth had no 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.
Do you think that the students conclusion is correct?
A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
The air layer of the atmosphere whose temperature is less than the hot layer behave as optically:
Refraction of light by the earth’s atmosphere due to variation in air density is called ____________.
Explain the refraction of light through a triangular glass prism using a labelled ray diagram. Hence define the angle of deviation.
