Page 1 - Lesson Note
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SAI INTERNATIONAL SCHOOL
                                                         Class-6

                                                      Lesson Note
                                                   Subject-Physics
                                             Ch-Electricity and Circuits

                                                   Subtopic- Torch
               Torch:
               A torch is a portable electric lamp which uses two or more cells to light a small bulb.
               It is a common example of a simple circuit.
               Components of a torch
                     Wire and spring: The wire connects the bulb and the switch whereas the spring
                       connects the cell and the switch.
                     One end of wire is connected to a terminal of the bulb and other to the switch.
                     Cells: The cells are placed between a terminal of the bulb and the spring. The
                       positive terminal of the battery points towards the bulb.
                     Switch: The switch controls the link between the wire and the spring.
                     Bulb


















               Working of a torch:

                     In the ON position, the metal strip under the switch touches both the wire and the
                       spring.
                     Thus, all the parts of the torch are connected in a closed path;It allows electricity
                       to flow through the bulb. The filament(made of tungsten metal) of the bulb gets
                       hot and gives us light.
                     In the OFF position, the metal strip loses contact with one of the wires. This
                       forms an open circuit and breaks the flow of current. Thus, the bulb does not
                       glow.
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