A siren emits sound of frequency 1000 Hz, it moves away from the observer towards a cliff with a speed of 10 ms-1 . Then, the frequency of sound heard by observer coming directly from the siren is

Question

A siren emits sound of frequency 1000 Hz, it moves away from the observer towards a cliff with a speed of 10 ms-1 . Then, the frequency of sound heard by observer coming directly from the siren is (A) less than 1000 Hz (B) greater than 1000 Hz (C) equal to 1000 Hz (D) no sound is heard

Tardigrade Admin · Accepted Answer

Sound heard beginarrayl f 1= f 0(( v / v + v s )) v s =10 ms -1 f 1=((330/330+10)) × 1000 f 1=(33/34) × 1000 text is less than 1000 Hz endarray

Q. A siren emits sound of frequency $1000 Hz$ , it moves away from the observer towards a cliff with a speed of $10 m s^{- 1}$ . Then, the frequency of sound heard by observer coming directly from the siren is

less than 1000 Hz

greater than 1000 Hz

equal to 1000 Hz

no sound is heard

Sound heard
$< b r / > < b r / > f_{1} = f_{0} (\frac{v}{v + v _{s}}) < b r / > v_{s} = 10 m s^{- 1} < b r / > f_{1} = (\frac{330}{330 + 10}) \times 1000 < b r / > f_{1} = \frac{33}{34} \times 1000 is less than 1000 Hz < b r / > < b r / >$

Q. A siren emits sound of frequency 1000Hz, it moves away from the observer towards a cliff with a speed of 10ms−1 . Then, the frequency of sound heard by observer coming directly from the siren is