173116 With what velocity should an observer approach a stationary sound source, so that the apparent frequency of sound should appear double the actual frequency ? ( $v$ is velocity of sound)

173117 Two sources $A$ and $B$ are sounding notes of frequency $680 \mathrm{~Hz}$. A listener moves from A to $B$ with a constant velocity $u$. If the speed of sound $340 \mathrm{~m} / \mathrm{s}$, what must be the value of $u$ so that the hears 10 beats per second?

172931 Two cars are moving towards each other at the speed of $50 \mathrm{~ms}^{-1}$. If one of the care blows a horn at a frequency of $250 \mathrm{~Hz}$, the wave length of the sound perceived by the driver of the other car is
(Speed of sound in air $=\mathbf{3 5 0} \mathrm{m} \mathrm{s}^{-1}$ )

172946 An engine is moving on a circular path of radius $200 \mathrm{~m}$ with speed of $15 \mathrm{~m} / \mathrm{s}$. What will be the frequency heard by an observer who is at rest at the centre of the circular path, when engine blows the whistle with frequency $250 \mathrm{~Hz}$ ?

173116 With what velocity should an observer approach a stationary sound source, so that the apparent frequency of sound should appear double the actual frequency ? ( $v$ is velocity of sound)

173117 Two sources $A$ and $B$ are sounding notes of frequency $680 \mathrm{~Hz}$. A listener moves from A to $B$ with a constant velocity $u$. If the speed of sound $340 \mathrm{~m} / \mathrm{s}$, what must be the value of $u$ so that the hears 10 beats per second?

172931 Two cars are moving towards each other at the speed of $50 \mathrm{~ms}^{-1}$. If one of the care blows a horn at a frequency of $250 \mathrm{~Hz}$, the wave length of the sound perceived by the driver of the other car is
(Speed of sound in air $=\mathbf{3 5 0} \mathrm{m} \mathrm{s}^{-1}$ )

172946 An engine is moving on a circular path of radius $200 \mathrm{~m}$ with speed of $15 \mathrm{~m} / \mathrm{s}$. What will be the frequency heard by an observer who is at rest at the centre of the circular path, when engine blows the whistle with frequency $250 \mathrm{~Hz}$ ?

173116 With what velocity should an observer approach a stationary sound source, so that the apparent frequency of sound should appear double the actual frequency ? ( $v$ is velocity of sound)

173117 Two sources $A$ and $B$ are sounding notes of frequency $680 \mathrm{~Hz}$. A listener moves from A to $B$ with a constant velocity $u$. If the speed of sound $340 \mathrm{~m} / \mathrm{s}$, what must be the value of $u$ so that the hears 10 beats per second?

172931 Two cars are moving towards each other at the speed of $50 \mathrm{~ms}^{-1}$. If one of the care blows a horn at a frequency of $250 \mathrm{~Hz}$, the wave length of the sound perceived by the driver of the other car is
(Speed of sound in air $=\mathbf{3 5 0} \mathrm{m} \mathrm{s}^{-1}$ )

172946 An engine is moving on a circular path of radius $200 \mathrm{~m}$ with speed of $15 \mathrm{~m} / \mathrm{s}$. What will be the frequency heard by an observer who is at rest at the centre of the circular path, when engine blows the whistle with frequency $250 \mathrm{~Hz}$ ?

173116 With what velocity should an observer approach a stationary sound source, so that the apparent frequency of sound should appear double the actual frequency ? ( $v$ is velocity of sound)

173117 Two sources $A$ and $B$ are sounding notes of frequency $680 \mathrm{~Hz}$. A listener moves from A to $B$ with a constant velocity $u$. If the speed of sound $340 \mathrm{~m} / \mathrm{s}$, what must be the value of $u$ so that the hears 10 beats per second?

172931 Two cars are moving towards each other at the speed of $50 \mathrm{~ms}^{-1}$. If one of the care blows a horn at a frequency of $250 \mathrm{~Hz}$, the wave length of the sound perceived by the driver of the other car is
(Speed of sound in air $=\mathbf{3 5 0} \mathrm{m} \mathrm{s}^{-1}$ )

172946 An engine is moving on a circular path of radius $200 \mathrm{~m}$ with speed of $15 \mathrm{~m} / \mathrm{s}$. What will be the frequency heard by an observer who is at rest at the centre of the circular path, when engine blows the whistle with frequency $250 \mathrm{~Hz}$ ?