Will the wavelength decrease when the wave moves from a light string to a heavy...


by insertnamehere
Tags: decrease, heavy, light, moves, string, wave, wavelength
insertnamehere
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#1
Sep15-05, 06:13 PM
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hi, i was just wondering if a wave's wavelength will change when it goes from a light string to a heavier one. I think it wouldn't affect it, however I know that velocity will be affected as the linear density will be changed. But am I right, will the wavelength remain unaffected?
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Tom Mattson
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#2
Sep15-05, 08:10 PM
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You're right that the speed changes. It seems that the essential piece of information that you are missing is this: the frequency does not change.

So since you know that [itex]v_1=\lambda_1f_1[/itex] and [itex]v_2=\lambda_2f_2[/itex], so what can you say about the wavelengths?
insertnamehere
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#3
Sep15-05, 08:56 PM
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ok, so that means that although the mass of the string increases, this will have no affect whatsoever on the frequency because since
v= sqrt(T/linear density) and also (wavelength/tension)
and increasing the mass of the string will have no affect on the tension, v increases as the tension remains constant, therefore will the wavelength have to INCREASE in order to compensate the equation? Am i on the right track?

Tom Mattson
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Sep15-05, 09:45 PM
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Will the wavelength decrease when the wave moves from a light string to a heavy...


Quote Quote by insertnamehere
v= sqrt(T/linear density) and also (wavelength/tension)
The first part is right, but the second part is not. v does not equal (wavelength/tension). That expression doesn't even have the right units to be a speed.

and increasing the mass of the string will have no affect on the tension, v increases as the tension remains constant, therefore will the wavelength have to INCREASE in order to compensate the equation? Am i on the right track?
The wave speed decreases as you move to the string of higher mass density.
insertnamehere
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#5
Sep16-05, 03:08 PM
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oh no, i meant v= (wavelength/PERIOD)


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