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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.
Explain why the planets do not twinkle.
Name two effects produced by the atmospheric refraction.
Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is:
sunrise advanced?
Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is:
sunset delayed?
State whether the following statement is true or false:
The planets twinkle at night due to atmospheric refraction of light.
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 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
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.
Do you think that the students conclusion is correct?
Why does the sky appear blue on a clear day?
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
A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
The stars appear higher from horizon than they actually are. Explain why it is so.
Explain why the planets do not twinkle but the stars twinkle.
Explain the refraction of light through a triangular glass prism using a labelled ray diagram. Hence define the angle of deviation.
