$A$ bat moving at $10\,ms^{-1}$ towards a wall sends a sound signal of $8000\,Hz$ towards it. On reflection it hears a sound of frequency $f$. The value of $f$ in $Hz$ is close to (speed of sound $= 320\,ms^{-1}$)

An observer and a source emitting sound of frequency $120 \,Hz$ are on the $X$-axis. The observer is stationary while the source of sound is in motion given by the equation $x=3 \sin \omega t$ (where $x$ is in metres and $t$ is in seconds). If the difference between the maximum and minimum frequencies of the sound observed by the observer is $22 \,Hz$,then the value of $\omega$ is (speed of sound in air $=330 \,ms^{-1}$):

$A$ car sounding a horn of frequency $1000 \ Hz$ passes a stationary observer. The ratio of the frequencies of the horn noted by the observer before and after the passing of the car is $11 : 9$. If the speed of sound is $v$,what is the speed of the car?

$A$ source is stationary and the observer is in motion along a line joining the source and the observer. If the frequency heard by the observer is $1\%$ higher than the true frequency,the ratio of velocity of the observer and that of sound in air is:

Obtain the equation for the frequency observed by a stationary observer when the source is moving.

The frequency changes by $10 \%$ as a sound source approaches a stationary observer with constant speed $V_s$. What would be the percentage change in the frequency as the source recedes from the observer with the same speed $\left(V_s < V\right)$ (in $.5$)?