Page 1 - HA-scattering of light
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Objective Questions:


                       1.  At sun rise or at sun set the sun appears to be reddish while at mid-day it
                          looks white. This is because
                          (a)  Scattering due to dust particles and air molecules causes this
                              phenomenon
                          (b)  The sun is cooler at sun rise or at sunset
                          (c)  Refraction causes this  phenomenon
                          (d)  Diffraction sends red rays to the earth at these times.
                       2.  ..............causes the blue colour of sky and the reddening of the Sun at
                          sunrise and sunset.
                       3.  Assertion : Blue colour of sky appears due to scattering of blue colour.
                          Reason : Blue colour has shortest wave length in visible spectrum.
                       4.  Assertion : The stars twinkle while the planet do not.

                          Reason : The stars are much bigger in size than the planets.
                       5.  Assertion : The  twinkling  of  stars  is  due  to  the  fact that refractive
                          index of the earth’s atmosphere fluctuates.
                          Reason : In cold countries, the phenomenon of looming (i.e., ship appears
                          in  the  sky)  takes  place,  because  refractive  index  of  air  decreases  with
                          height.

                       6.  Assertion : The sky looks dark and black instead of blue in outer  space.
                            Reason  :  No  atmosphere  containing  air  in  the  outer    space  to  scatter
                      sunlight.

               Subjective Questions:


                       7. Why does the sky appear black or dark to an astronaut instead of blue?

                       8. Which colour of light scatters more and why?

                       9. Which colour of light has shorter wave length and which colour of light has
                       larger wave length among the visible lights?

                       10. Why does deep sea water appear blue?


                       11.How much time blue light scatters than the red light?
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