Where Does the Intensity of Sound Waves Go in Complete Silence?

AI Thread Summary
In a scenario with two speakers producing identical sound waves that create complete destructive interference at a midpoint, there is no resultant sound intensity, resulting in silence. The concept of "lost" intensity is not applicable, as intensity relates to wave properties like power and area. Instead, the air particles at the midpoint exchange momentum, slightly increasing their kinetic energy. This energy exchange may cause a negligible rise in temperature, but it would not lead to any discomfort or pain for a listener. Overall, the discussion emphasizes that silence in this context is a product of wave cancellation, not a loss of energy.
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If we set two speakers far apart, giving identical sound waves having intensity of threshold of pain, in such a way that at midway between them, there is complete destructive interference. Would there any intensity of sound there in complete silence? If not, then where is "lost" intensity gone? Would that " silence" cause any pain?
 
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Intensity is the rate at which a wave transfers energy per unit area. If there is complete destructive interference midway between the speakers, then there will be no resultant wave propagation there, so the rate of energy transfer also equals 0(silence). Intensity is a relation between the characteristic properties of a wave (in this case power and area), and as such terms like "lost" do not apply to it in this case. Since the waves cancel each other midway, you can say that the air particles simply exchange some momentum and raise each other's kinetic energy of vibration over there. Whether that silence causes discomfort or not is entirely up to the listener.
 
Intensity is the rate at which a wave transfers energy per unit area. If there is complete destructive interference midway between the speakers, then there will be no resultant wave propagation there, so the rate of energy transfer also equals 0(silence). Intensity is a relation between the characteristic properties of a wave (in this case power and area), and as such terms like "lost" do not apply to it in this case. Since the waves cancel each other midway, you can say that the air particles simply exchange some momentum and raise each other's kinetic energy of vibration over there. Whether that silence causes discomfort or not is entirely up to the listener.
 
PWiz said:
Intensity is the rate at which a wave transfers energy per unit area. If there is complete destructive interference midway between the speakers, then there will be no resultant wave propagation there, so the rate of energy transfer also equals 0(silence). Intensity is a relation between the characteristic properties of a wave (in this case power and area), and as such terms like "lost" do not apply to it in this case. Since the waves cancel each other midway, you can say that the air particles simply exchange some momentum and raise each other's kinetic energy of vibration over there. Whether that silence causes discomfort or not is entirely up to the listener.
So if they increase each other's kinetic energy then the temperature of that area should increase! Isn't it?
 
By a negligible amount, yes.
 
PWiz said:
By a negligible amount, yes.
Thanks for clarification
 
If you shout for 8 years, the energy could heat up a cup of coffee. So you can imagine by how little the temperature will rise in this case.
 
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