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The loudness, L, measured in decibels (Db), of a sound intensity, I, measured in watts per square meter, is defined as where and is the least intense sound a human ear can hear. Jessica is listening to soft music at a sound intensity level of 10-9 on her computer while she does her homework. Braylee is completing her homework while listening to very loud music at a sound intensity level of 10-3 on her headphones. How many times louder is Braylee's music than Jessica's?

User Alex Wally
by
7.4k points

2 Answers

6 votes

Answer:

Taking the course on edge? Don't sweat it brotha.

Explanation:

The answer is B. 3 times louder

User Rosstex
by
8.6k points
3 votes

Answer:

Barlyee's music is 3 times louder than Jessica's.

Explanation:

We know that, loudness is measured as,


L = 10 * log (I)/(I_o)

So let us measure the loudness of music that Jessica is listening to,


L = 10 * log (10^(-9))/(10^(-12))=10 * log {10^3}= 10 * 3 log 10= 30 dB

So Jessica is listening to music at 30dB.

And the loudness of music that Barylee is listening to,


L = 10 * log (10^(-3))/(10^(-12))= 10 * log {10^9}= 10 * 9 log 10= 90 dB

So Barylee is listening to music at 90dB.


90=3 * 30

Therefore, the music that Barylee is listening to, is 3 times louder than the music Jessica is listening to.

User Scragz
by
8.7k points
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