Sound source $A$ is located at $x=0,y=0,$ and sound source $B$ is located at $x=0,y=3\mathrm{.}30m.$ The two sources radiate coherently and in phase. An observer at $x=15\mathrm{.}0m,y=0$ notes that as he takes a few steps from $y=0$ in either the $+y$ or $-y$ direction, the sound intensity diminishes.

What is the lowest frequency $f_1$ of the sources that can account for that observation?

$f_1=$

$$

Incorrect Answer

What is the second$-$lowest frequency $f_2$ of the sources that can account for that observation?

$f_2=pro{d}_{\text{I}\text{n}\text{c}\text{o}\text{r}\text{r}\text{e}\text{c}\text{t}\text{A}\text{n}\text{s}\text{w}\text{e}\text{r}}kHz$

Sound source $A$ is located at $x=0,y=0,$ and sound source $B$ is located at $x=0,y=3\mathrm{.}30m.$ The two sources radiate coherently and in phase. An observer at $x=15\mathrm{.}0m,y=0$ notes that as he takes a few steps from $y=0$ in either the $+y$ or $-y$ direction, the sound intensity diminishes.

What is the lowest frequency $f_1$ of the sources that can account for that observation?

$f_1=$ubrace$(ubrace{)}_{\text{I}\text{n}\text{c}\text{o}\text{r}\text{r}\text{e}\text{c}\text{t}\text{A}\text{n}\text{s}\text{w}\text{e}\text{r}}kHz$

What is the second$-$lowest frequency $f_2$ of the sources that can account for that observation?

$f_2=$

kHz