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tuning forks illustration
    
  Appears In
      
      Detangling Light-based Thermometers with Combs
      
            Demonstration of a “beat” pattern with two tuning forks that are almost identical but slightly off from each other in tone. If you play them at the same time, the tones will interfere with each other and create beating, where the sound gets alternately loud and soft.

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Credit
                                Sean Kelley/NIST HEADQUARTERS
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