## Re: Help me understand why sound is one dimensional

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Reply #73 –

I'd like to point out that I think much of the confusion here is regarding the usage of the word "dimension". The *graph* of a one-variable function y = f(x) is indeed two-dimensional (that is, you need two dimensions to draw the function) even if you only have *one* independent variable x.

To the OP; you say in your first message, "I would assume sound also has at least two axis, one representing time" -- that is absolutely correct, sound is a wave that propagates through space and time, so you need at least one spatial independent variable and the time independent variable; a third variable also exists here, the pressure, which is the *dependent* variable, which, when the wave equation is solved, gives the pressure as a function of time and space.

Then you say, "My friend makes the claim that there only is one". Could it be possible your friend is thinking of the typical expansion-compression cycle, like that of a Slinky, which goes back and forth in one *spatial* dimension but otherwise also advances in time?

As others here have pointed out, it'd be useful to see, verbatim, what your friend says, from which we can attempt to deduce what was meant, and if needed, correct what they said.