Question

Spherical sound waves are emitted uniformly in all directions from a point source. The variation in sound level SL as a function of distance ‘r’ from the source can be written as
Where a and b are positive constants.

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

$SL=10Log\frac{I}{I_0}$
$=10log\frac{k}{I_0{r}^2}$
$=10logK-10log\left(I_0{r}^2\right)$
$=10logk-10log{I}_0-20logr$
= a – b log r