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3 years ago

10

A speaker emits sound waves in all directions, and at a distance of 28 m from it the intensity level is 73 db. What is the total

power put out by the speaker, in watts?

1 answer:

Oduvanchick [21]3 years ago

6 0

Answer:

P=0.197 Watt

Explanation:

Given That

B=73dB

Io= 1 * 10^-12

$I=Io * 10^{\frac{B}{10} } \\I=2 * 10^{-5} Wm^{-2} \\A=4 * pi * r^{2}\\ A=9852.03 m^{2}\\ Power= I * A\\P= 0.197 Watt$

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