Length and Distance

Sound Waves

Why does the intensity of a sound decrease as the distance from the source increases?

## Answer

###### Wiki User

###### May 22, 2017 7:14PM

- the waves spread out over a larger area
- the waves are absorbed by the medium as they pass through it
- the waves are being scattered by irregularities in the medium and don't all proceed forward
- etc.

## Related Questions

###### Asked in Jobs & Education, Physics, Education

### Why does the intensity decrease with the square of the distance from a point source?

Intensity is defined as energy per unit area. As we move away
from the point source, the area over which the energy distributes
is generally spherical or hemispherical. The area of a sphere or
hemisphere increases proportional to the square of radius, where
the radius in this case is the distance from the point source. Thus
Intensity, which is inversely proportional to area, decreases with
the square of distance.
Hope it was clear. Visit MechMinds.ca for any further help!

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### What happens to the intensity of light the farther it gets from its source?

The intensity of light decreases by what astronomers call "the
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distance). So, if a person was standing at a distance D from the
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intensity of light will decrease by a factor of the square of 3,
9.

###### Asked in Science

### How are distance and light intensity related?

The intensity of light observed from a source of constant
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Thus, if I double the distance to a light source the observed
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### What is the relationship between intensity of the radiation given off from a radiation source and distance from the radiation source?

The source doesn't care how far you are from it, or whether
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###### Asked in Physics, Science Experiments

### By what factor will the sound of a source change the intensity of the waves if the distance is tripled from the sound source?

For sound intensity (acoustic
intensity) we use in the free field (direct field) the inverse
square law = 1/r². I1 and r1 belong to the close distance and I2
and r2 belong to the far distance.
I2 = I1 * (r1/r2)²
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Three times farther away gives
one ninth the sound
intensity of the close sound intensity.

###### Asked in Physics, Waves Vibrations and Oscillations, Sound Waves

### What is the maximum distance at which the riveter is still audible?

The intensity of a sound produced by a point source decreases as
the square of the distance from the source. Consider a riveter as a
point source of sound and assume that the intensities listed in
Table 12.1 are measured at a distance 1 m away from the source.
What is the maximum distance at which the riveter is still audible?
(Neglect losses due to energy absorption in the air.)