Page 1 - Lesson Notes- Electric Bulb
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SAI INTERNATIONAL SCHOOL

                                                        Class 6
                                                   Lesson Notes
                                                 Subject- Physics

                                          Ch. – Electricity and Circuits
                                             Subtopic- Electric Bulb



               Electric blub:
                      Bulb is a device that converts electrical energy into heat and light energy.
                      Construction:
                          o It consists of transparent glass covering, coiled metal wire known as
                              the filament made up of tungsten metal.
                          o It is filled with inert gases such as argon, neon etc.
                      Working:
                          o When electricity flow through the filament, it gets heated up and glows
                              to give light.


























               (Note:

                      Tungsten metal is used to make filament of the bulb because of the following
                       reason:
                                  Tungsten metal have high melting point
                                  It also has high resistance due to which it can produce high
                                     amount of heat.
                      Importance of transparent glass covering in electric bulb:
                               The glass covers the filament and the inert gas present in it

                                 prevents filament from reacting with oxygen which will lead to
                                 breaking of filament.
                               Glass is transparent which allows the light to pass.
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