Page 137 - Active Science 5 Ebook and Activity
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Properties of a Shadow
           Some of the important properties of a shadow are:

         1.  A shadow is formed on the surface which is on the other side of the light source.
         2.  A shadow does not give the details of an object. Only the outline or the shape of an
              object is shown by its shadow.

         3.  A shadow is always dark. The colour of the shadow is not the same as that of the object.

         4.  The size of a shadow varies by changing the distance between an object and source
              of light. It also depends on the distance between an object and the surface on which
              a shadow forms.



        Let’s Recapitulate

            Tick the correct statements.

            1.  Transparent objects form shadows.                                                          _____
            2.  A light source is necessary for the formation of a shadow.                                 _____

            3.  Opaque objects form a pale shadow.                                                         _____
            4.  The colour of the shadow is the same as that of the object.                                _____


        To understand how the size of a shadow varies on changing the distance between object

        and the source of light, you can perform the following activity.


        Activity 12.3

        Aim                      :    To know how the size of a shadow varies on changing the distance
                                      between the object and the source of the light.

        Materials Required:    Take an opaque object and a source of light.
        Procedure                :  •  Turn off the light of the room. Place the object in front of a wall and

                                      project light on the object. See the shadow of the object on the wall.
                                   •  Now move the source of light near the object and again notice the
                                      shadow of the object.

        Observation              :    You will observe that the size of the shadow changes on changing the

                                      distance between the object and the source of light.
                                                           Shadow                                  Shadow
                                         Source                                       Source
                                                        Object                                   Object






                                                              Screen                                  Screen



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