Waves Homework help -- Waves on a String

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Homework Help Overview

The discussion revolves around a problem related to waves on a string, specifically focusing on the relationships between wavelength, frequency, and wave speed. Participants are attempting to clarify their understanding of these concepts in the context of a given problem statement.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are discussing the calculation of wave speed using the relationship between wavelength and frequency. There are attempts to derive frequency and wavelength based on given values, but some participants express uncertainty about the correctness of these calculations. Questions arise regarding the completeness of the problem statement and whether additional context about the string is necessary.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the problem statement and expressing confusion about the information provided. Some guidance has been offered regarding the need for a clear problem statement, and there are indications that participants are exploring different interpretations of the data presented.

Contextual Notes

There is mention of a graph showing the displacement of a point on the string over time, but participants note that it does not provide sufficient information to derive wave speed or wavelength without additional context. The discussion highlights potential missing information that could affect the understanding of the problem.

Riemannenthusiast
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Homework Statement
I attached an image
Relevant Equations
lamba*frequency=wave speed
1/f=speed
Okay well I'm stuck on this one. I know that lamba times frequency is wave speed and 1/f is period. I think that the wavelength of the wave is four but what is the frequency? (1/2)? Would I multiply 4*1/2 to get 2 m/s as the wave speed and then if the frequency doubles to .25, the wavelength be 8m? I think I am missing something because I don't think that's the proper way to find the frequency. Is there something special about the string?
 

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The "Homework Statement" is where you tell us the question or problem. Rather than have us take a wild guess at what you're trying to do!
 
A homework statement is the problem statement: the question the way it was asked of you. It is extremely helpful in introducing us to the problem so we know what you are talking about. As it is, I can not make heads nor tails out of your question.
 
PeroK said:
The "Homework Statement" is where you tell us the question or problem. Rather than have us take a wild guess at what you're trying to do!
Oh okay, thank you!
 
Cutter Ketch said:
A homework statement is the problem statement: the question the way it was asked of you. It is extremely helpful in introducing us to the problem so we know what you are talking about. As it is, I can not make heads nor tails out of your question.
Gotcha. I attached a picture of the question :)
 
Hmmm ... I can see why you are stuck. Is this the whole problem? Was there some prior related statement about the string in this problem?
 
Cutter Ketch said:
Hmmm ... I can see why you are stuck. Is this the whole problem? Was there some prior related statement about the string in this problem?
I took a screenshot of the answer choices...will that help?
 
Riemannenthusiast said:
the wavelength of the wave is four
You might want to rethink that. Also, you should not state wavelength without units.
 
I see that it expects numeric answers, not just relative comparisons.

The problem is very clear what is plotted. The string is stretched horizontally. The transverse wave propagates horizontally. The graph shows the vertical (i.e. transverse) displacement of a single point on the string as a function of time. From this one can only derive the frequency and the amplitude. I do not believe it is possible to relate these to the speed or wavelength without additional information. The problem is flawed.
 
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  • #10
Do you think that I could do distance over time to find wave speed. Like the wave traveled 4 meters in 2 seconds so its speed is 2 m/s and then if the frequency doubles from .5 to 1, the period is one and the wavelength would be 2m?
 
  • #11
Riemannenthusiast said:
Do you think that I could do distance over time to find wave speed. Like the wave traveled 4 meters in 2 seconds so its speed is 2 m/s and then if the frequency doubles from .5 to 1, the period is one and the wavelength would be 2m?

What makes you think the wave traveled 4 m in 2 s? That information is not given in the problem statement nor can it be derived from the graph.
 
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