======Visualizing Sound Waves with an Oscilloscope======


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**Alternative titles:** Sound Wave Patterns
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====Summary====                   
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====Procedure====  
  - Connect a signal generator to both a speaker and an oscilloscope.
  - Adjust the oscilloscope’s timebase so the wave is clearly visible on the screen.
  - Produce a low-frequency sound and observe its long wavelength on the oscilloscope.
  - Increase the frequency and note how the wavelength shortens and pitch rises.
  - Adjust the amplitude on the signal generator and observe the taller or shorter waveforms, while noting that pitch does not change.
  - Compare different frequency ranges to illustrate the upper and lower limits of human hearing.
  - Discuss how sound properties are represented visually: frequency as spacing of waves, amplitude as wave height.



====Links==== 
Visualising sound waves with an oscilloscope - CLEAPSS: 
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Sound Waves with an Oscilloscope - Teacher Demos - Mr clark: 
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====Variations====
  * Use different waveforms (sine, square, triangle) and compare how they sound and appear.
  * Record a voice or musical instrument with a microphone connected to the oscilloscope.
  * Explore very low frequencies where the sound is felt as vibration rather than heard.



====Safety Precautions====
  * Keep speaker volume at safe levels to protect hearing.
  * Avoid prolonged exposure to high frequencies, which may cause discomfort or damage.
  * Handle oscilloscope and signal generator carefully, following lab electrical safety rules.




====Questions to Consider====
  * How does the oscilloscope trace change as frequency increases? (The waves get closer together, representing higher pitch.)
  * How is amplitude shown on the oscilloscope? (By the height of the wave.)
  * Why does amplitude affect volume but not pitch? (Amplitude changes wave energy, while pitch depends only on frequency.)
  * What frequencies can humans typically hear, and how does this change with age? (Roughly 20 Hz to 20 kHz; the upper range decreases with age.)