# Homework Help: Sound Intensity Level Ratio

1. Apr 22, 2008

### tbontom

[SOLVED] Sound Intensity Level Ratio

1. The problem statement, all variables and given/known data

The sound intensity level at a rock concert is 110 dB, while that at a jazz fest is 100 dB. Determine the ratio of the sound intensity at the rock concert to that at the jazz fest.

2. Relevant equations
B=(10dB) log(I/Io)

3. The attempt at a solution

110=(10db) log (I/1.0*10^-12)
100=(10db) log (I/1.0*10^-12)

dont know where to go from here

2. Apr 22, 2008

### cristo

Staff Emeritus
Ok, well let I_0=10^-12, then you have two expressions (taking log base 10)

$$110=10\log\left(\frac{I_1}{I_0}\right) \hskip1cm 100=10\log\left(\frac{I_2}{I_0}\right)$$ and you want to find the ratio $$\frac{I_1}{I_2}$$. So, you need to perform some algebra on these expressions to make I_1 and I_2 the subject of the equations, respectively. Try dividing both sides of each equation by 10. After that you will need to take the inverse log of each side: how would you do this?

3. Apr 22, 2008

### tbontom

That was my problem, I forgot you could do antilogs. thanks you so much

4. Apr 22, 2008

### cristo

Staff Emeritus
No problem!