Can a travelling wave be nonlinear?

[shanepitts]

I'm am almost certain that the answer to this question is "yes". If so, what in nature can be a nonlinear traveling wave?

 

[Simon Bridge]

Yes - i.e. it may travel through a nonlinear medium.
You should be able to work out an equation for a nonlinear traveling wave by comparing bthe definition of "travelling wave" with that of "nonlinear equation".
http://en.wikipedia.org/wiki/Nonlinear_system#Examples_of_nonlinear_equations

 

[sophiecentaur]

Look up Solitons. They are waves that propagate for long distances and maintain their shape because of a combination of non-linearity and dispersion.

 

[Simon Bridge]

... although the result may be less obvious considering the level the question is being asked at.
https://www.physicsforums.com/threads/is-a-given-expression-a-travelling-wave.793693/

At this level there is a certain amount of painful learning and checking things - it's good discipline, which is why there is this tendency to answer this sort of question with "work it out for yourself". ;)