Page 1 - Lesson Notes
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SAI INTERNTIONAL SCHOOL
                                                        Class 8
                                                    Lesson notes
                                                 Subject- Physics
                                        Ch- Some Natural Phenomena
                                               Subtopic- Lightning




                   LIGHTNING: The bright flash of light which we see in the clouds as a result of
                   electric discharge is called lightning.


                         The electric discharge in the atmosphere is either between the clouds
                          or between the earth and the ground.
                         There are two types of lightning: 1)Sheet lightning 2) Fork lightning
                         Sheet lightning: It is between the clouds having opposite charge.
                         Fork lightning: It is between the clouds and the ground.

                   Lightning Conductor: It is the device installed on the buildings to protect it
                   from lightning.

                         Construction: It is a metallic rod installed at the top of building during
                          the construction. The rod is attached to a copper strip whose other end
                          is buried under the ground.
                         Working: When lightning strikes a building, it first strikes the metal rod
                          and will be conducted to the ground through the metal strip. This way
                          buildings remains safe from the lightning.
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