B M Sharma Solutions for Chapter: Sound Wave And Doppler Effect, Exercise 2: DPP

A curve is plotted to represent the dependence of the ratio of the received frequency $f$ to the frequency $f_0$ emitted by the source, on the ratio of the speed of observer $V_{ob}$ to the speed of sound ${\mathrm{V}}_{\text{sound }}$, in a situation in which an observer is moving towards a stationary sound source. The curve is best represented by:

The difference between the apparent frequency of a source of sound, as perceived by an observer during its approach, and recession is $2\%$ of the natural frequency of the source. If the velocity of sound in air is $300 \mathrm{m} {\mathrm{s}}^{-1}$, the velocity of the source is (It is given that velocity of source $<<$ velocity of sound)

Two cars are moving on two perpendicular roads towards a crossing, with uniform speed of $72 \mathrm{km} {\mathrm{h}}^{-1}$ and $36 \mathrm{km} {\mathrm{h}}^{-1}$. If the first car blows horn of frequency $280 \mathrm{Hz}$, then the frequency of the horn heard by the driver of second car, when line joining the cars make $45°$ angle with the roads, will be
 

A police car moving at $22 \mathrm{m} {\mathrm{s}}^{-1}$, chases a motorcyclist. The policeman sounds his horn at $176 \mathrm{Hz}$, while both of them move towards a stationary siren of frequency $165 \mathrm{Hz}$. Calculate the speed of the motorcycle, if it is given that, he does not observes any beats.

A car is initially at rest, $330 \mathrm{m}$ away from a stationary observer. It begins to move towards the observer with an acceleration of $1.1 \mathrm{m} {\mathrm{s}}^{-2}$, sounding its horn continuously. $20 \mathrm{seconds}$ later, the driver stops sounding the horn. The velocity of sound in air is $330 \mathrm{m} {\mathrm{s}}^{-1}$. The observer will hear the sound of the horn for a duration of

Two persons $A$ and $B$, each carrying a source of frequency $596 \mathrm{Hz}$ and $600 \mathrm{Hz}$, respectively, are standing at rest, a few $\mathrm{metres}$ apart. $A$ starts moving towards $B$ with a velocity of $2 \mathrm{m} {\mathrm{s}}^{-1}$. If the speed of sound is $300 \mathrm{m} {\mathrm{s}}^{-1}$, which of the following statement is true?

A sound wave of frequency $\nu$ travels horizontally to the right. It is reflected from a large vertical plane surface, moving to the left with a speed $v$. If the speed of sound in the medium is $c$, then study the following statements.

A car moves towards a hill with speed $v_c$. It blows a horn of frequency $f$, which is heard by an observer following the car with speed $v_0.$ The speed of sound in air is $v$.