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Sound Intensity Propagation and Sound Waves
- Thread starter Nunzio Luigi
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In summary, the conversation touched upon the topic of sound waves and the inverse square law. The speaker mentioned that sound waves do not respond to a law but rather it is our understanding and observation of the waves that leads to the inverse square law. This law is explained by the fact that the surface area of a wave front increases with the square of the distance from the source.
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BvU
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Hello Luigi, 
" Right ? " is not a good question to ask on PF. Just like "No" is not a good answer.
Sound waves do not 'respond to a law'. We describe what we observe from spherical sound waves by what we call an inverse square law. And the explanation is that the surface of a wave front increases with the square of the distance to the source (*). So whatever disturbance it is that propagates outwards: when it is twice as far away it has to disturb four times as much. Far enough from the source the disturbance can not be distinguished from random noise any more.
" Right ? " is not a good question to ask on PF. Just like "No" is not a good answer.
Sound waves do not 'respond to a law'. We describe what we observe from spherical sound waves by what we call an inverse square law. And the explanation is that the surface of a wave front increases with the square of the distance to the source (*). So whatever disturbance it is that propagates outwards: when it is twice as far away it has to disturb four times as much. Far enough from the source the disturbance can not be distinguished from random noise any more.
(*) the surface area of a sphere with radius ##r## is ##4\pi r^2##
Related to Sound Intensity Propagation and Sound Waves
1. What is sound intensity and how is it measured?
Sound intensity refers to the amount of energy that is transmitted per unit time through a unit area in the direction of sound propagation. It is measured in units of watts per square meter (W/m^2) and can be measured using specialized instruments such as sound level meters or microphones.
2. How does sound intensity affect the loudness of a sound?
The higher the sound intensity, the louder the sound will be perceived. The human ear can detect a wide range of sound intensities, from 0 dB (threshold of hearing) to 120 dB (threshold of pain). A sound that is 10 times more intense will be perceived as twice as loud by the human ear.
3. What factors affect the propagation of sound waves?
The propagation of sound waves can be affected by several factors, including the medium through which the sound travels (such as air, water, or solids), the temperature and humidity of the medium, and the presence of obstacles or barriers that can reflect or absorb sound waves.
4. Can sound travel in a vacuum?
No, sound cannot travel in a vacuum because it requires a medium for its propagation. In a vacuum, there are no molecules or particles to vibrate and transmit the sound energy. However, electromagnetic waves, such as light, can still travel through a vacuum.
5. How do sound waves interact with each other?
Sound waves can interact with each other in different ways, depending on their amplitudes and frequencies. They can interfere constructively, where the amplitudes of the two waves add up to produce a louder sound, or destructively, where the amplitudes cancel out and produce a quieter sound. This phenomenon is known as superposition and plays a crucial role in various acoustic phenomena, such as beats and standing waves.
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