Page 1 - HA-recombination of white light
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Objective Questions:


               1.Rainbow is caused due to
                          (a)  Reflection of sun light air
                          (b)  Dispersion of sun light from water drops
                          (c)  Refraction of sun light from water drops
                          (d)  Diffraction of sun rays from water drops
               2. Assertion : Secondary rainbow is fainter than primary rainbow.
                   Reason : Secondary rainbow formation is three step process and hence, the
               intensity of light is reduced at the second reflection inside the rain drop.

               3. Assertion : A rainbow is sometimes seen in the sky      in rainy season only
               when observer’s back is towards the sun.
               Reason : Internal reflection in the water droplets  cause dispersion and the final
               rays are in backward direction.
               4. Assertion : Rainbow is an example of the dispersion of sunlight by the water
               droplets.
               Reason : Light of shorter wavelength is scattered much more than light of larger
               wavelength.



                Subjective Questions:


                 5. Explain the formation of rainbow.

                 6. Why dispersion does not occur through a glass slab?
                 7. What is the difference between a primary and secondary rainbow?
                 8. Which color is there at the top of a primary rainbow?
                 9. Is rainbow a complete circle?
                 10. What do you mean by recombination of colours?
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