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SAI INTERNATIONAL SCHOOL
                                                         Class 8
                                                     Lesson Notes
                                                   Subject-Physics
                                                       CH-Sound
                                        Subtopic-Terms Related to sound




               Terms related to sound wave


                  1. Amplitude:
                       Maximum distance of the vibrating particle from its mean position.
                       SI unit is meter.

                  2. Wavelength:
                       Distance between two consecutive compression or rarefaction.
                       SI unit is meter.

                  3. Frequency:
                       Number of vibrations per second.
                       SI unit is hertz (Hz).


                  4. Wave speed:
                       Distance covered by sound wave per unit time.
                       SI unit is 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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