A certain source of sound waves radiates uniformly in all directions. At a distance of 20 m from...
Question:
A certain source of sound waves radiates uniformly in all directions. At a distance of 20 m from the source, the intensity level is 51 dB.
a) What is the intensity (in {eq}W/m^2 {/eq}) of the sound waves at that distance from the source? (Note: The reference intensity {eq}I0 {/eq} is {eq}1.0 \times 10^{-12}\ W/m^2 {/eq}.)
b) What is the total acoustic power output of the source, in watts?
Sound Intensity Level:
Sound intensity levels denote a given sound wave's sound intensity in terms of decibels (dB). The sound intensity level (SIL) is the basis of the loudness of a sound. The SIL is a function of the intensity of the wave itself, and it can be determined as:
{eq}\displaystyle \rm \beta = 10log_{10} \left(\frac{I}{1\ \times\ 10^{-12}\ W/m^2}\right) {/eq}
where:
- {eq}\displaystyle \rm I {/eq} is the intensity of the sound
Answer and Explanation: 1
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Given:
- {eq}\displaystyle r = 20\ m {/eq} is the distance from the source
- {eq}\displaystyle \beta = 51\ dB {/eq} is the sound intensity level
- {eq}...
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Intensity in Physics: Definition & Measurement
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Chapter 5 / Lesson 10
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This lesson explains what wave intensity in physics is, and it explains the intensity of light formula with examples. This lesson also describes how to calculate intensity of sound waves.
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