Intensity of the superposition of sound waves

AI Thread Summary
The discussion focuses on calculating the intensity of two sound waves interfering destructively, with one wave at 4 mW/m2 and the other at 10 mW/m2. The correct approach involves subtracting the intensities rather than adding them, as destructive interference reduces the overall intensity. Participants clarify that the intensity of the superposition is found by taking the square root of each intensity, subtracting the resulting values, and then squaring the final result. The confusion arises from incorrectly adding the intensities instead of subtracting them. The final intensity of the superposition should reflect the destructive nature of the interference.
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Homework Statement


A sound wave with intensity 4 mW/m2 interferes destructively with a sound wave that has an intensity of 10 mW/m2. What is the intensity of the superposition of the two?


Homework Equations



sqrt of both values

The Attempt at a Solution


i believe that taking the sqrt of both values then adding them then squaring them is the correct solution but i keep getting the incorrect answer.

i keep getting 26.65
 
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Why are you adding? The question says that the interference is destructive.
 
ok so what exactly do i do then?
 
Subtract, don't add, since the interference is destructive.
 

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