Help w/ constructive interference sound wave intensity

[ryanjdiaz]

The Problem : The sound wave with intensity 31 mW/m2 interferes constructively with a sound wave that has an intensity of 20 mW/m2. What is the intensity of the superposition of the two.


I know that you can add the amplitudes for constructive interference or subtract for destructive interference . Also i do know that intensity is proportional to amplitude squard. I don't know how to solve when i only have two intensities so i know you can't just add the intensitites. any help would be appreciated thanks



[

 

[denverdoc]

This may be a bit of a trick question; if the two waves were set up with equal amplitudes to collide constructively, what would be your guess? Double, nothing, or somewhre in between? Pressure is a scalar quantity,