What is the equation for standing wave patterns and why is the solution 0?

AI Thread Summary
The discussion revolves around understanding the equation for standing wave patterns, specifically y = 2yocos(wt)sin(Kx), in the context of a viola. The user is confused about obtaining a result of zero when calculating sin(0), which indicates a nodal point where there is no vertical movement of the string. It is clarified that this outcome is expected at x = 0, where the string is attached. The conversation emphasizes that x and t are variables that change, affecting the height of the string at different positions and times. Overall, the analysis confirms that the equation accurately models the behavior of the string, particularly at nodal points.
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Homework Statement



Hi everyone. I am working on a physics research paper on Standing Wave Patterns and the physics of a viola. I found this formula for standing wave patterns and am having trouble making sense of it. When I tried, I got sin(0) which is 0 making the whole thing 0. Is this a valid equation and am I missing something?

w = 2764
t = (1/440)

k = 2pi/wavelength
x = distance traveled.

I am sorry, but I am really confuesed

Homework Equations



y = 2yocos(wt)sin(Kx)



The Attempt at a Solution



2yo (2764)(1/440) = 2p1
cos 2 pi = 1
sin (0) = 0

= Ahh!

I may be using the variables wrong, but I used 2pi * frequency to get w, 1/frequency to get t
 
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y(x,t) = 2yocos(wt)sin(Kx) is the function which is dependent on both time and position. t is not the period.

It's perfectly reasonable to get 0 a nodal points.
 
I don't know the formula y = 2yocos(wt)sin(Kx) so perhaps I shouldn't be offering any help.
But it seems clear to me that the sin(kx) = 0 at x = 0 is just telling you that there is no vertical movement of the string at x = 0. That would be the position where the string is attached. It seems a very reasonable result!
 
Okay. Thanks.

Excuse my ignorance, we had to research a topic that we haven't covered, but would it be more appropriate to use x as the string length, since that is further from where the string is attached and would cause vertical movement? I am not really understanding what I proved by getting 0...well I don't really understand what I am proving anyway.
 
The equation you listed is modeling a string in two dimensions that is time dependent. So you can think of the function giving you the height of the string at some distance x, and some time t.

x and t are variables that change.

You proved that when sin(kx) = 0 then the height of the string is also 0. This makes sense since at x=0 there is a node.
 
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