When the observer 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 speed of sound in air and $F_1/F_2 = 2$, then $V/V_1 =$

$A$ siren emitting sound of frequency $500 \; Hz$ is going away from a static listener with a speed of $50 \; m/s$. The frequency of sound heard by the listener is .... $Hz$. (Take speed of sound $v = 330 \; m/s$)

Doppler's effect will not be applicable when the velocity of sound source is

$A$ train is moving towards a stationary observer with speed $34 \text{ m/s}$. $A$ train sounds a whistle of frequency $450 \text{ Hz}$. If the speed of sound is $340 \text{ m/s}$, the frequency heard by the observer in Hz is

$A$ racing car moving towards a cliff sounds its horn. The driver observes that the sound reflected from the cliff has a pitch one octave higher than the actual sound of the horn. If $v$ is the velocity of sound,the velocity of the car will be

$A$ sound source is tied to one end of a string of length $50 \ cm$ and is rotated with an angular speed of $40 \ rad \ s^{-1}$ in a horizontal plane. The ratio of the maximum and minimum frequencies of the sound heard by an observer standing at a distance of $10 \ m$ from the fixed end of the string is (speed of sound in air $= 340 \ m \ s^{-1}$).