How many times larger is the intensity of a sound if you move from 20 m away from it to a distance of 2m?
I think I'm supposed to use the ratio (r1/r2)^2, but I don't know which is which; I don't even know if that's the correct formula.
you are moving it a distance of ten times, so intensity increases 100 times. Isn't that 10 db?
I think so, so I divide the current distance by the new one and square, right? because that's what I'm getting from the equation, so, I think I get it, thank you! :)
To find the change in intensity of a sound as you move from one distance to another, you can use the inverse square law formula, which states that the intensity of a sound is inversely proportional to the square of the distance from the source.
The formula can be written as:
I2/I1 = (r1/r2)^2
where:
I1 is the initial intensity
I2 is the final intensity
r1 is the initial distance from the source
r2 is the final distance from the source
In your case, you are given that the initial distance from the sound source is 20m (r1) and the final distance is 2m (r2). Let's assume that the initial intensity is I1. The question asks how many times larger the intensity is when you move from 20m to 2m.
You want to find I2/I1, so let's plug in the values we know into the formula:
I2/I1 = (r1/r2)^2
I2/I1 = (20/2)^2
I2/I1 = 10^2
I2/I1 = 100
This means that the intensity of the sound is 100 times larger when you move from a distance of 20m to 2m.