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SAI INTERNATIONAL SCHOOL
                                                          Class8
                                                     Lesson Notes
                                                   Subject-Physics
                                                       CH-Sound
                                        Subtopic-Terms Related to sound




               NOTES

               Terms related to sound wave
                  1.  amplitude: Maximum distance of the vibrating particle from its mean position.
                       SI unit is: metre
                  2.  Wavelength: Distance between two consecutive compression or rarefaction
                       SI unit = metre
                  3.  Frequency: Number of vibrations per second.
                       SI unit = hertz(Hz)
                  4.  Wave speed: Distance covered by sound wave per unit time.
                       SI unit =m/s
                  [formula: wave speed = wavelength * frequency. ]
                  (speed of sound in air is 330m/s)

               5. Time Period: The time a vibrating body takes to complete one vibration is called its

               time period.It is denoted by the  letter ‘T’. SI unit : second

                  [If ‘f’ is the  frequency of vibrating body the time period  T =1/f.]
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