Wave Equation After Reflection

AI Thread Summary
The discussion focuses on the wave equation Acos(kx-wt) after reflection from a wall. It clarifies that the phase change (∅) occurs when the wave reflects, resulting in a positive wt to indicate the wave's new direction. A more accurate representation of the reflected wave is suggested as A*cos(-kx + ωt + φ'), highlighting its movement in the negative x direction. The properties of cosine allow for the sign change to be absorbed into the phase shift φ. This understanding is crucial for accurately describing wave behavior post-reflection.
elemis
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What do the components of the following equation represent :

http://www.mediafire.com/view/?0we6f9jkw26qi9o

To be clear, this represents a wave of the form Acos(kx-wt) after being reflected off a wall.

I understand that the ∅ represents the phase change of the wave after hitting the wall. The wt is now positive instead of negative because it is traveling in the opposite direction.

Is this a correct description or have I missed something out ?
 
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Seems about right. But I would point out that the actual reflected wave would be something like, A\cos\left(-kx+\omega t + \phi'\right) to actually signify that the wave is moving in the negative x direction due to the reflection. One can then use the properties of the cosine to flip the sign of the argument and absorb the sign change in \phi' into \phi.
 
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