Constructive Wave Interference: Can Two Waves Combine?

[Bashyboy]

Hi,

I was wondering if two waves, whom both have the same frequency and wave, could be combined together in a constructive interference way, even if they did not have the same amplitude?

 

[Doc Al]

Sure, why not?

 

[Bashyboy]

Well, my book made it seem as though constructive waves could be formed when the amplitude, frequency, and wavelength are the same. Thank you, by the way, for your prompt reply.

 

[Doc Al]

Well, my book made it seem as though constructive waves could be formed when the amplitude, frequency, and wavelength are the same.

Well, the part about needing the same amplitude is not true for constructive interference. Now, to get completely destructive interference you do need the same amplitude, otherwise the out of phase waves would not completely cancel each other.

 

[olivermsun]

You can always remind yourself how this works by going back to the mathematics, e.g.,

$$\cos \omega t + 3 \cos \omega t = ?$$