A police car moving at $22 m/s$, chases a motorcyclist. The police man sounds his horn at $176 Hz$, while both of them move towards a stationary siren of frequency $165 Hz$. Calculate the speed of the motorcycle, if it is given that he does not observes any beats .... $m/s$
A$33$
B$22$
C$0$
D$11$
IIT 2003, Diffcult
Download our app for free and get started
B$22$
b (b) ${n_1}$ = Frequency of the police car horn observer heard by motorcyclist
${n_2}$ = Frequency of the siren heard by motorcyclist.
$v_2$ = Speed of motor cyclist
${n_1}$ = $\frac{{330 - v}}{{330 - 22}} \times 176\,\,;\,\,{n_2} = \frac{{330 + v}}{{330}} \times 165$
$\because {n_1} - {n_2} = 0 \Rightarrow v = 22 m/s$.
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.*
Ultrasonic signal sent from $SONAR$ returns to it after reflection from a rock after a lapse of $1 \,sec.$ If the velocity of ultrasound in water is $1600 ms^{-1}$, the depth of the rock in water is ..... $m$
It takes $2.0$ seconds for a sound wave to travel between two fixed points when the day temperature is ${10^o}C.$ If the temperature rise to ${30^o}C$ the sound wave travels between the same fixed parts in ...... $sec$
A closed pipe of length $10 \,cm$ has its fundamental frequency half that of the second overtone of an open pipe. The length of the open pipe ......... $cm$
A motorcyclist going around a circular track of radius $50\ m$ with a speed of $25\ m/s$ , is at a point $X$. A static siren at $Y$ is emitting sound of frequency $n$. How many times (approximately) in an hour will the motor cyclist hear the sound of actual frequency $Y$ ?
The equation of a stationary wave along a stretched string is given by $y = 5\,sin\, \frac{2\pi }{3}x\, cos\, 40\pi t$ where $x$ and $y$ are in $cm$ and $t$ is in $s$. The separation between two adjacent nodes is ..... $cm$
A student is experimenting with resonance tube apparatus in Physics lab to find the speed of sound at room temperature. He got first two resonating lengths of air column as $17\, cm$ and $51 \,cm$, using tuning fork of frequency $512\, Hz$. Find speed of sound at room temperature ..... $m/s$
If the speed of the wave shown in the figure is $330m/s$ in the given medium, then the equation of the wave propagating in the positive $x-$direction will be (all quantities are in $M.K.S.$ units)
The wavelength of sound waves in hydrogen gas corresponding to the lower limit of audibility is ........ $m$ (speed of sound in hydrogen gas is about $1350 \,m / s$ )