Sound Intensity on a Field (no interference)

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Ethan_Tab
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Homework Statement


Two loudspeakers on elevated platforms are at opposite ends of a field. Each broadcasts equally in all directions. At the halfway point, the intensity is 74.1dB.

What is the sound intensity level at a point one-quarter of the way from one speaker to the other along the line joining them?

Assume no interference and sound loss.

Homework Equations


Ia/Ib=rb2/ra2

The Attempt at a Solution


I've started by finding the sound intensity at the half way point in W/m^2

107.41=Ia/10-12
Therfore: Ia= 2.57e-5 w/m^2
Since this is the net sum of the two speakers each one only provides half of that therefore just before they combine, the Sound intensity at the half way point relative to each speaker is
1.28e-5 W/m^2

Do I just use this information to figure out Ib at 1/4th the distance with the equation I wrote down in Part 2?
 
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Ethan_Tab said:
I've started by finding the sound intensity at the half way point in W/m^2

107.41=Ia/10-12
Therfore: Ia= 2.57e-5 w/m^2
Since this is the net sum of the two speakers each one only provides half of that therefore just before they combine, the Sound intensity at the half way point relative to each speaker is
1.28e-5 W/m^2

OK

Do I just use this information to figure out Ib at 1/4th the distance with the equation I wrote down in Part 2?

Sounds good.