If a source emitting waves of frequency $f$ moves towards an observer with a velocity $v/4$ and the observer moves away from the source with a velocity $v/6$,the apparent frequency as heard by the observer will be ($v =$ velocity of sound).

When both source and listener are approaching each other,the observed frequency of sound is given by (where $V$ is the speed of sound,$V_L$ and $V_S$ are the velocities of the listener and source respectively,and $n_0$ is the radiated frequency):

When the listener moves towards a stationary source with velocity $V_1$,the apparent frequency of the emitted note is $F_1$. When the observer moves away from the source with velocity $V_1$,the apparent frequency is $F_2$. If $V$ is the velocity of sound in air and $\frac{F_1}{F_2} = 2$,then find the ratio $\frac{V}{V_1}$.

$A$ source of sound $A$ emitting waves of frequency $1800\,Hz$ is falling towards the ground with a terminal speed $v.$ The observer $B$ on the ground directly beneath the source receives waves of frequency $2150\,Hz.$ The source $A$ receives waves,reflected from the ground,of frequency nearly ..... $Hz$ (Speed of sound $= 343\,m/s$)

$A$ source and an observer approach each other with the same velocity $50 \, m/s$. If the apparent frequency is $435 \, s^{-1}$,then the real frequency is .... $s^{-1}$ (Take speed of sound $v = 332 \, m/s$)

The speed of sound in air at a given temperature is $350 \, m/s$. An engine blows a whistle at a frequency of $1200 \, cps$. It is approaching the observer with a velocity of $50 \, m/s$. The apparent frequency in $cps$ heard by the observer will be: