(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The displacement of particles in a string stretched in the x direction is represented by y. Which of the following expressions for y describe wave motion:

1: cos kx sin wt

2:[tex]k^2x^2-w^2t^2[/tex]

3:[tex]cos^2(kx+wt)[/tex]

2. Relevant equations

Equation of a progressive wave is of the form [tex]y=f(t-\frac{x}{v})[/tex]

3. The attempt at a solution

The first equation represents a standing wave. The second obviously cant be it (its not of the form f(t-x/v) ). But I thought the third one would represent the equation of a progressive wave. It doesnt though. Why?

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# Wave Equation

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