Page 1 - Lesson Note-Torch
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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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