SOUND WAVES
Did you know  that a sound wave  is created  when a whole lot of  pressure waves move though the air. Sound vibrates at very different rates  or frequencies as they travel.

Sound waves of all differnt kinds all travel at the same rate in the same medium.   Since sound is a form of energy, it can always be changed from one form to another.Did you know that other forms of energy can be turned into sound. For example, sound energy can be turned to electrical energy.   The way a telephone works demonstrates this in action.

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