engine emits sound uniformly in all directions, radiating an acoustic power of 3.65 × 10 5 W. 3.65×105 W. Find the intensity of the sound at a distance of 52.7 m 52.7 m from

Answer :

Answer:

130.2dB

Explanation:

The formula for determining the intensity of a wave is expressed as

[tex]I=\frac{P}{A}\\[/tex]

Where P is the power in watts, and A is the area of the sphere formed by the wave

Data given

Power,P=3.65*10^5W

distance,d=52.7

Hence since the distance represent the radius, we can determine the area of the sphere formed

[tex]A=4\pi r^{2}\\A=4\pi *52.7^{2}\\A=34900.45m^2[/tex]

The intensity can be computed as

[tex]I=\frac{3.65*10^5}{34900.45}\\ I=10.46W/m^2[/tex]

we can convert to decibel

[tex]I=10log\frac{10.46}{10^{-12}} \\I=130.2dB[/tex]

Answer:

10.46W/m²

Explanation:

The intensity (I) of a sound is related to the power (P) radiated by the sound within an area (A) as follows;

I = [tex]\frac{P}{A}[/tex]              ----------------(i)

But;

A = 4[tex]\pi[/tex] r²

Where;

r is the specified distance covered by the sound.

Substitute A = 4 [tex]\pi[/tex] r² into equation (i) to get;

I = [tex]\frac{P}{4\pi r^{2} }[/tex]               ------------------------(ii)

From the question;

P = acoustic power = 3.65 x 10⁵W

r = 52.7m

To calculate the intensity of the sound, take [tex]\pi[/tex] = 3.142 and substitute other values into equation (ii) as follows;

I = [tex]\frac{3.65*10^5}{4*3.142*52.7^2}[/tex]

I = [tex]\frac{3.65*10^5}{34904.98}[/tex]

I = 10.46W/m²

Therefore, the intensity of the sound at that distance is 10.46W/m²

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