Solving Intensity and Power Homework: 100 m, 126 mW

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The discussion revolves around a homework problem involving sound intensity and power from a spherical sinusoidal source. The intensity at a distance of 10.0 m is given as 1.00 × 10−4 W/m2, and participants confirm that the intensity of 1.00 × 10−6 W/m2 occurs at 100 m from the source. The power radiated by the source is debated, with one participant suggesting 126 mW, which is confirmed as correct despite initial confusion over units. Clarification is provided that the answers are in milliwatts, not megawatts. The conversation emphasizes understanding sound intensity and power calculations in physics.
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Homework Statement



A spherical sinusoidal source radiates sound uniformly in all directions. At a distance 10.0m the sound intensity level is 1.00 × 10−4 W/m2.

1. At what distance from the source is the intensity 1.00 × 10−6 W/m2?
A. 1 m
B. 10 m
C. 100 m
D. 1 km


2. What is the power radiated by this source?
A. Pav = 208 mW
B. Pav = 126 mW
C. Pav = 332 mW
D. Pav = 412 mW



Homework Equations





The Attempt at a Solution



I got 1 as 100 m and 2 as 126 watt, but I am not sure about the 2nd answer. So please help me. Thanks
 
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Both answers are correct. Why did you doubt your second answer?
 
I doubt the 2nd answer because I get 0.126 watt, but the answer is in megawatt
 
Did you get what i amsaying
 
The answers are in milliwatts, not megawatts.
 

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