The source producing sound and an observer both are moving along the direction of propagation of sound waves. If the respective velocities of sound, source and an observer are $v, {v_s}$ and ${v_o}$, then the apparent frequency heard by the observer will be ($n =$ frequency of sound)
Easy
Download our app for free and get started
(b) As both observer and source are moving in the direction of sound, so the velocities are as per sing convention are positive.
So, the apparent frequency is given as
$n^{\prime}=n \frac{\left(v-v_{0}\right)}{\left(v-v_{s}\right)}$
Download our appand 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.*
Similar Questions
- 1Frequency of tuning fork $A$ is $256\,Hz$ . It produces four $beats/sec$ . with tuning fork $B$ . When wax is applied at tuning fork $B$ then $6\,beats/sec$ . are heard. By reducing little amount of wax $4\,beats/sec$ . are heard. Frequency of $B$ is .... $Hz$View Solution
- 2A closed and an open organ pipe have same lengths. If the ratio of frequencies of their seventh overtones is $\left(\frac{a-1}{a}\right)$ then the value of $a$ isView Solution
- 3A steel rod of length $100\, cm$ is clamped at the middle. The frequency of the fundamental mode for the longitudinal vibrations of the rod is ..... $kHz$ (Speed of sound in steel $= 5\, km\, s^{-1}$)View Solution
- 4Unlike a laboratory sonometer, a stringed instrument is seldom plucked in the middle. Supposing a sitar string is plucked at about $\frac{1}{4}$th of its length from the end. The most prominent harmonic would beView Solution
- 5In a transverse wave the distance between a crest and neighbouring trough at the same instant is $4.0\, cm$ and the distance between a crest and trough at the same place is $1 .0\, cm$ . The next crest appears at the same place after a time interval of $0.4\,s$. The maximum speed of the vibrating particles in the medium isView Solution
- 6View SolutionA big explosion on the moon cannot be heard on the earth because
- 7A source of sound $S$ is moving with the velocity of $50\,m/s$ towards a stationary observer. The observer measures the frequency of the sound as $1000\,Hz.$ What will be the apparent frequency of the source when it is moving away from the observer after crossing him ... $Hz$ ? (Take velocity of sound in air is $350\,m/s$ )View Solution
- 8In a city sound intensity level increases uniformly by about $1\ dB$ annually. How many years will it take for intensity of sound to become double ..... $year$View Solution
- 9The equation of a wave is $y = 2\sin \pi (0.5x - 200t)$, where $x$ and $y$ are expressed in $cm$ and $t$ in $sec.$ The wave velocity is ...... $cm/sec$View Solution
- 10A string of length $1\,\,m$ and linear mass density $0.01\,\,kgm^{-1}$ is stretched to a tension of $100\,\,N.$ When both ends of the string are fixed, the three lowest frequencies for standing wave are $f_1, f_2$ and $f_3$. When only one end of the string is fixed, the three lowest frequencies for standing wave are $n_1, n_2$ and $n_3$. ThenView Solution