Sound as a Pressure Wave

This is intended to help clarify the concept of sound as a wave and in particular what amplitude means.

You should be able to shift-click-drag on either axis to zoom in or out on that axis and shift-click-drag elsewhere to move the graph around.

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Set AtmosphericPressure to 0 by dragging the dot on the line below the name to the left. Now use the same method to change the amplitude. What is the connection between the amplitude = number and the behavior of the blue line below it?

Adjust the amplitude and AtmosphericPressure so that the bottom of the wave just touches the horizontal axis. Now adjust the frequency. What is the connection between the frequency = number and the times on the horizontal axis?

Now change the AtmosphericPressure to something non-zero. How can you get the values of the highest and lowest points on the sound wave (in Pa) from the amplitude and AtmosphericPressure numbers?

Lenore Horner, Created with GeoGebra