Question

What is the intensity of a sound which has a sound level of 35 dB?

Answer 1

You can use the relationship:
`I(dB)=10log(I/I_0)`
Where `I_0=10^(-12) W/m^2` represents the intensity just audible (correspnding to `0 dB`).
So:
`35=10log(I/10^(-12))`; power `10` both sides and rearrange:
`I=3.2xx10^-9 W/m^2`