Finding amplitude from a diagram

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    Amplitude Diagram
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Discussion Overview

The discussion revolves around determining the amplitude and wavelength of waves from a diagram presented in an AQA Physics A AS textbook exercise. Participants are exploring how to extract these values from the provided information, which includes phase differences.

Discussion Character

  • Homework-related
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant expresses uncertainty about how to find the amplitude and wavelength from the diagram, noting they can find phase differences but not the other values.
  • Another participant suggests that amplitude is defined as the distance from the center line to the highest point on the graph, but points out that the lack of a vertical axis makes this determination impossible.
  • A different participant proposes using a table, phase difference formula, and trigonometry to find the values, but mentions not arriving at the correct answer.
  • One participant criticizes the representation in the textbook, suggesting it complicates what should be simple questions and expresses confusion about scaling the plots.
  • Concerns are raised about the interpretation of 'Distance from 0' in the chart, with a suggestion that it refers to horizontal distance rather than vertical.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on how to extract the amplitude and wavelength from the diagram, with multiple competing views and uncertainties expressed throughout the discussion.

Contextual Notes

There are limitations noted regarding the diagram, including the absence of a vertical axis and unclear scaling, which may affect the ability to determine amplitude and wavelength accurately.

Googl
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Hi all,

This is not homework or coursework. I am not sure whether this question would be classed as homework or coursework because it is neither.

I am using the AQA Physics A AS textbook and attempting exercise 12.2 on page 177. In I am stuck on question 4 and I have absolutely no idea on how to find the amplitude. I have spent almost a day but still I haven't been able to find a matching answer. I was hoping someone here might help me.

Here is the full question:

For the waves in Figure 4,

a) determine i the amplitude and wavelength, ii the phase difference between P and R, iii the phase difference between P and S.

I can find the phase differences but not the wavelength and amplitude. I am probably missing something or have missed something and I am looking for a hint.

I managed to find a preview of the page here

I managed to get a screenshot of the page:
wave1.png


Thank you.
 
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The amplitude is the distance from the center line to a highest point on the graph. You can't tell from the graph because there is no vertical axis.
 
Hi,

I think you can by using the table, the phase difference formula and trigonometry. I have tried that but I don't get the right answer.
 
googl
here are two sketches that illustrates what you are looking for...

If you understand the definition, the concept, I would not waste further time on this silly representation.

http://en.wikipedia.org/wiki/Transverse_wave

good lord...They have managed to take a few simple questions and turn them to a convoluted
interpretation...

What phase difference did you find??

I have no idea how to scale the plots..either vertically or horizontally.

'Distance from 0' as provided in the chart is actually incorrect...what they mean is the 'x' [horizontal distance] from o...

I hope the concepts in the rest of the text are presented more clearly than here!
 

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