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3 years ago

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You are listening to the radio when one of your favorite songs comes on, so you turn up the volume. If you managed to increase t

he sound intensity by
17.0 dB, by what factor did the intensity of the sound, in W/m2, increase?
The intensity of sound, in W/m2, increased by a factor of .

1 answer:

andrew-mc [135]3 years ago

5 0

To solve this problem we need to apply the corresponding sound intensity measured from the logarithmic scale. Since in the range of intensities that the human ear can detect without pain there are large differences in the number of figures used on a linear scale, it is usual to use a logarithmic scale. The unit most used in the logarithmic scale is the decibel yes described as

$\beta_{dB} = 10log_{10} \frac{I}{I_0}$

Where,

I = Acoustic intensity in linear scale

$I_0$ = Hearing threshold

The value in decibels is 17dB, then

$17dB = 10log_{10} \frac{I}{I_0}$

Using properties of logarithms we have,

$\frac{17}{10} = log_{10} \frac{I}{I_0}$

$log_{10} \frac{I}{I_0} = 1.7$

$\frac{I}{I_0} = 10^{1.7}$

$\frac{I}{I_0} = 50.12 W/m^2$

Therefore the factor that the intensity of the sound was $50.12W/m^2$

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Answer:

Option D.) 0.09 I₀

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The intensity, I, of a polarized light after passing through a polarizing filter is given by $I = I_{0} cos^{2} \theta$

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4 years ago

The radius of the aorta is «10 mm and the blood flowing through it has a speed of about 300 mm/s. A capillary has a radius of ab

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Answer:

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(II). The approximate number of capillaries is $3.74\times10^{9}$

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Where. v₁ = speed of blood in capillarity

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$A_{1}=A_{2}\times\dfrac{v_{2}}{v_{1}}$

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Using formula of area of cross section

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