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Waves
Waves

Sound Level (Decibels)

β=10log⁡10II0\beta = 10\log_{10}\frac{I}{I_0}

Logarithmic scale for sound intensity.

Variables

β
Sound level
In decibels
dB
I
Intensity
Sound intensity
W/m²
I₀
Reference intensity
10⁻¹² W/m²
W/m²

Derivation

β = 10 log₁₀(I/I₀) where I₀ = 10⁻¹² W/m².

Your notes

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Common questions

What is the Sound Level (Decibels) formula?

Sound Level (Decibels) is written β= 10log₁₀I/I₀. Logarithmic scale for sound intensity. It belongs to Waves, under Sound Waves.

What are the units in β= 10log₁₀I/I₀?

In SI units, β is sound level, measured in dB; I is intensity, measured in kg/s³; I₀ is reference intensity, measured in kg/s³.

How is the Sound Level (Decibels) formula derived?

β = 10 log₁₀(I/I₀) where I₀ = 10⁻¹² W/m². The result is β= 10log₁₀I/I₀.