Answer:
far from the speaker the intensity drops to 85 dB.
Explanation:
In the equation for the Decibel scale
The ratio of the intensities can be written as
And since
and
,
meaning
Putting this into equation (1), we get:
Now, if the intensity is 100 dB when the distance is 5 meters, we have:
by taking both sides to the exponent:
Now equation (2) becomes
when the intensity level is 85 dB we have
take both sides to exponents and we get:
Thus, far from the speaker the intensity drops to 85 dB.