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3 years ago

The standard measure used to compare sound intensities is the ______ .

Physics

2 answers:

german3 years ago

6 0

Answer: Decibels

Explanation:

Decibel is the unit which used to measure intensity of sound. Sound intensity is the power carried by the sound waves per unit area perpendicular to it.

$I = \frac{P}{A}$ measured in W/m²

In decibels:

$I (dB) = 10 log_{10}\frac{I}{I_o}$

With each unit rise of decibel, the sound intensity varies by a factor of 10.

uranmaximum [27]3 years ago

4 0

The answer is Decibels. <span />

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given,

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depth of water when amplitude is down to 1 μV/m

Intrinsic impedance of air = 120 π Ω

Intrinsic impedance of water = $\dfrac{120\pi}{\epsilon_r}$

Using equation to solve the problem

$E(z) = E_0 e^{-\alpha\ z}$

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