What does the A stand for in this equation?

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    Amplitude
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Discussion Overview

The discussion revolves around the interpretation of the variable 'A' in the equation y=A\sin{(kx-t\omega)} and explores related concepts such as the relationship between the wave number 'k' and wavelength, as well as the relationship between angular frequency 'ω' and the time period 'T' of the wave. The scope includes conceptual clarification and mathematical reasoning.

Discussion Character

  • Conceptual clarification
  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • Some participants propose that 'A' represents the amplitude of the wave.
  • Others suggest that 'A' signifies the maximum value of the displacement from the mean position.
  • One participant inquires about the relationship between 'k' and the wavelength, leading to the expression k=\frac{2\pi}{\lambda}.
  • A participant explains that the wavelength is the distance between successive crests or troughs, and relates 'k' to the periodic nature of sine waves.
  • Another participant seeks to find a relationship between 'ω' and the time period 'T', starting from the equation y=A\sin{(kx-t\omega)}.
  • One participant mentions that 'ω' is related to frequency 'f' through the equation ω = 2 \pi f, and that T = \frac{2 \pi}{\omega}.
  • There is a challenge raised regarding whether the discussion constitutes homework assistance.

Areas of Agreement / Disagreement

Participants generally agree on the interpretation of 'A' as amplitude, but there are differing views on the nature of the discussion, with some seeing it as homework help while others do not. The relationships between 'k', 'ω', and 'T' are discussed, but the inquiry into these relationships remains open-ended.

Contextual Notes

There are unresolved aspects regarding the derivation of relationships between 'ω' and 'T', and the discussion does not reach a consensus on whether the inquiries are considered homework-related.

BLUE_CHIP
What does the [tex]A[/tex] stand for in the equation:

[tex]y=A\sin{(kx-t\omega)}[/tex]



CHEERS :)
 
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Amplitude.

- Warren
 
max value of the displacement from the mean position
 
thanks :)

but could you answer this

whats the relationship between [tex]k[/tex] and the wavelength of the wave
 
[tex]k=\frac{2\pi}{\lambda}[/tex]
 
Think about it. If x is the displacement along a taught string, the wavelength of a wave on that string is the distance between successive crests or troughs.

All sine waves repeat every 2 pi radians.

When [itex]x = \lambda[/itex], you want the argument to be [itex]2 \pi[/itex].

Try rewriting the first term (the term with the x) as:

[tex]\frac{2 \pi x}{\lambda}[/tex]

You'll see that when [itex]x = \lambda[/itex], the entire expression is [itex]2 \pi[/itex] -- exactly one period. This is the right expression.

Therefore, if you want to simplify that expression by bringing in a new symbol k, k must be

[tex]k = \frac{2 \pi}{\lambda}[/tex]

- Warren
 
Last edited:
Score! thanks Boudoir
 
Bummer hit a brick wall again. check this out:

for the equation [tex]y=A\sin{(kx-t\omega)}[/tex] find a relationship between [tex]\omega[/tex] and the time period [tex]T[/tex] of the wave.

when [tex]t=T[/tex] [tex]y=0[/tex] and [tex]x=0[/tex]

therefore:

[tex]A\sin{(-T\omega)}=0[/tex]

but then what?
 
Don't you have a textbook?

[tex]\omega = 2 \pi f[/tex]

[tex]T = \frac{1}{f}[/tex]

[tex]T = \frac{2 \pi}{\omega}[/tex]

- Warren
 
  • #10
Originally posted by chroot
Don't you have a textbook?


- Warren

I think you're doing his homework for him.
 
  • #11
I don't find it as Homework.

Anyway He is reaching the conclusions and that's the bottom line
 
  • #12
Thanks :smile: saved my life.
 

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