Page 1 - HA-atmospheric refraction
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Objective Questions:


               1.Stars appear twinkling in the sky:


               a) Due to density of atmospheric layesrs keeps on changing
               b) Due to atmospheric pressure
               c) Due to scattering of light
               d) Wind convection currents …
               2.Sunrise and sunset appears 2 minutes before and after actual sunrise and sunset?
               It is due to…
                   a)Scattering of light
                     b)Due to atmospheric refraction
                      c)Dispersion of light
                      d)Reflection of light
               3.The air layer of atmosphere whose temperature is less then the hot layer behave
               as optically
               a) denser medium
               b) rarer medium
               c) inactive medium
               d) either denser or rarer medium
               4. Refraction of light by the earth’s atmosphere due to variation in air density is
               called
               a) atmospheric reflection
               b) atmospheric dispersion
               c) atmospheric scattering
               d) atmospheric refraction


               5. Twinkling of stars is due to atmospheric [NCERT Exemplar Problems]
               a) dispersion of light by water droplets
               b) refraction of light by different layers of varying refractive indices
               c) scattering of light by dust particles
               d) internal reflection of light by clouds.


                Subjective Questions:


                   1.  Name the phenomenon which causes the twinkling of stars.
                   2.  How much time before and after the sun rise and sunset, we can see the sun?
                   3.  By how much time the day would have been shorter if the Earth had no
                       atmosphere.
                   4.  What is the colour of sunlight?

                   5.  Why does the sun appear flattened during sunrise/sunset?
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