$V_D=0$

College Physics Homework$-$Ch $17$

$0\mathrm{.}86$

$($ex$-$setup only$)$ While standing right next to a racetrack $|$ you measure the sound emitted by a moving car $.$ The frequency you measure is only $86\%$ of the frequency emitted by the car. Assume the speed of sound is $343\frac{m}{s}.($a$)$ Is the car moving away from you or toward you? Explain. $($b$)$ Determine the speed of the car.

$F_D=0\mathrm{.}86f_{S}a$