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प्रश्न
A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
उत्तर
A star sometimes appears brighter and some other times fainter, this effect is called as twinkling effect. This effect arises due to atmospheric refraction. Our atmosphere is constantly moving. Light travelling from the stars gets bent in different directions making them twinkle.
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?
Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is:
sunset delayed?
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 ................
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
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
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.
