A source of sound emits waves with frequency $f \,Hz$ and speed $V\, m/sec$. Two observers move away from this source in opposite directions each with a speed $0.2\, V$ relative to the source. The ratio of frequencies heard by the two observers will be
A$3:2$
B$2:3$
C$1:1$
D$4:10$
Easy
Download our app for free and get started
C$1:1$
c (c) Both listeners, hears the same frequencies.
Download our app
and get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
The beats are produced by two sound sources of same amplitude and of nearly equal frequencies. The maximum intensity of beats will be ...... that of one source
A tuning fork $A$ of frequency $200 Hz$ is sounded with fork $B,$ the number of beats per second is $5.$ By putting some wax on $A,$ the number of beats increases to $8.$ The frequency of fork $B$ is .... $Hz$
A train moves towards a stationary observer with speed $34\, m/s$. The train sounds a whistle and its frequency registered by the observer is $f_1$. If the speed of the train is reduced to $17\, m/s$, the frequency registered is $f_2$. If speed of sound is $340\, m/s$, then the ratio $f_1/f_2$ is
In order to double the frequency of the fundamental note emitted by a stretched string, the length is reduced to $\frac{3}{4}$$^{th}$ of the original length and the tension is changed. The factor by which the tension is to be changed, is
A pulse is generated at lower end of a hanging rope of uniform density and length $L$. The speed of the pulse when it reaches the mid point of rope is ......
Two tuning forks of frequencies $256$ and $258$ vibrations/sec are sounded together, then time interval between consecutive maxima heard by the observer is ..... $sec$
An air column in a pipe, which is closed at one end, will be in resonance with a vibrating body of frequency $166 \,Hz$, if the length of the air column is .... $m$
An earthquake generates both transverse $(S)$ and longitudinal $(P)$ sound waves in the earth. The speed of $S$ waves is about $4.5 \,km/s$ and that of $P$ waves is about $8.0 \,km/s.$ A seismograph records $P$ and $S$ waves from an earthquake. The first $P$ wave arrives $4.0\, min$ before the first $S$ wave. The epicenter of the earthquake is located at a distance about .... $km$
Two pulses in a stretched string whose centres are initially $8 cm$ apart are moving towards each other as shown in the figure. The speed of each pulse is $2 cm/s$. After $2$ seconds, the total energy of the pulses will be