Home
Class 11
PHYSICS
A whistle emitting a sound of frequency ...


A whistle emitting a sound of frequency `440 H`z is tied to string of `1.5 m` length and rotated with an angular velocity of `20 rad//sec` in the horizontal plane. Then the range of frequencies heard by an observer stationed at a large distance from the whistle will `(v=330 m//s)`

Text Solution

Verified by Experts

The correct Answer is:
`403.3 Hz` to 484 Hz
`Deltaf_(1)=f_(0)((v)/(v-v_(S)))=440((330)/(330-20xx1.5))=484Hz`
`f_(2)=f_(0)((v)/(v+v_(S)))=440((330)/(330+20xx15"))=403.3Hz`
Promotional Banner

Topper's Solved these Questions

  • WAVES AND OSCILLATIONS

    ALLEN |Exercise Part-1(Exercise-04)[B]|13 Videos

  • WAVES AND OSCILLATIONS

    ALLEN |Exercise Part-1(Exercise-05)[A]|28 Videos

  • WAVES AND OSCILLATIONS

    ALLEN |Exercise Part-1(Exercise-03)|31 Videos

  • SEMICONDUCTORS

    ALLEN |Exercise Part-3(Exercise-4)|50 Videos

Similar Questions

Explore conceptually related problems

A train approaching a hill at a speed of 40 km//hr sounds a whistle of frequency 580 Hz when it is at a distance of 1km from a hill. A wind with a speed of 40km//hr is blowing in the direction of motion of the train Find (i) the frequency of the whistle as heard by an observer on the hill, (ii) the distance from the hill at which the echo from the hill is heard by the driver and its frequency. (Velocity of sound in air = 1, 200 km//hr )

A uniform rod of mass m and length l rotates in a horizontal plane with an angular velocity omega about a vertical axis passing through one end. The tension in the rod at a distance x from the axis is

A source whistling a sound of frequency 450 Hz moves towards a stationary listener with a speed of 33 m/s. If velocity of sound is 333 m/s, then find frequency of sound heard by this listener.

A whistle of frequency 500 Hz tied to the end of a string of length 1.2 m revolves at 400 rev / min . A listener standing some distance away in the plane of rotation of whistle hears frequencies in the range (speed of sound = 340 m / s )

A siren emitting sound of frequency 800 Hz is going away from a static listener with a speed of 30 m/s. Frequency of the sound to be heard by the listener is (Take velocity of sound as 330 m/s)

A source of sound of frequency 256 Hz is moving towards a wall with a velocity of 5 m/s. How many beats per second will be heard by an observer O standing in such a positoin that the source S is between O and wall? (c=330(m)/(s) )

A whistle revolves in a circle with an angular speed of 20 rad//sec using a string of length 50 cm . If the frequency of sound from the whistle is 385 Hz , then what is the minimum frequency heard by an observer which is far away from the centre in the same plane? v=340m//s

A thin uniform metallic rod of length 0.5 m and radius 0.1 m rotates with an angular velocity 400rad/s is a horizontal plane about a vertical axis passing through one of its ends. Calculate (a) tenstion in the rod and (b) the elogation of te rod. The density of material of the rod is 10^(4)kg//m^(3) and the young's modulus is 2xx10^(11)N//m^(2)

A spot light S rotates in a horizontal plane with a constant angular velocity of 0.1 rad//s . The spot of light P move along the wall at a disatnce 3 m . What is the velocity of the spot P when theta = 45^(@) ?

ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-04)[A]
  1. A string vibrate according to the equation y = 5 sin ((pi x)/(3)) cos ...

    Text Solution

    |

  2. A bat emits ultrasonic sound of frequency 100 kHz in air. If this soun...

    Text Solution

    |

  3. The vibrations of a string of length 60cm fixed at both ends are repre...

    Text Solution

    |

  4. Given below are some functions of x and t to represent the displacemen...

    Text Solution

    |

  5. If the bulk modulus of water is 4000 MPa, what is the speed of sound i...

    Text Solution

    |

  6. A steel rod 100 cm long is clamped at its middle. The fundamental freq...

    Text Solution

    |

  7. Two successive resonance frequencies in an open organ pipe are 1944 Hz...

    Text Solution

    |

  8. A flute which we treat as a pipe open at both ends is 60 cm long. (a) ...

    Text Solution

    |

  9. A string 25cm long and having a mass of 2.5 gm is under tension. A pip...

    Text Solution

    |

  10. Two tuning fork having frequency 300 Hz & 305 Hz produce beat phenomen...

    Text Solution

    |

  11. Two sitar strings A and B playing the note 'Dha' are slightly out of ...

    Text Solution

    |

  12. A source of sound of frequency 256 Hz is moving towards a wall with a ...

    Text Solution

    |

  13. A person going away from a factory on his scooter at a speed of 36 km/...

    Text Solution

    |

  14. A car has two horns having a difference in frequency of 180 Hz. The ca...

    Text Solution

    |

  15. A whistle emitting a sound of frequency 440 Hz is tied to string of 1....

    Text Solution

    |

  16. Two tuning forks with natural frequencies of 340 Hz each move relative...

    Text Solution

    |

  17. A SONAR system fixed in a submarine operates at a frequency 40.0kHz. A...

    Text Solution

    |

  18. A sonometer wire under tension of 64 N vibrating in its fundamental mo...

    Text Solution

    |

  19. A train approaching a hill at a speed of 40 km//hr sounds a whistle of...

    Text Solution

    |

  20. A train of length l is moving with a constant speed v circular track o...

    Text Solution

    |