Home
Class 11
PHYSICS
A narrow sound pulse (for example, a sho...

A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium. (a) Does the pulse have a definite (i) wavelength, (ii) frequency, (iii) speed of propagation ? (b) If the pulse rate is `1` after every `20 s`, (i.e. the whistle is blown for a split second after every `20 s`) is the frequency of the note produced by the whistle equal to `(1)/(20) = 0.05 Hz` ?

Text Solution

Verified by Experts

(a) (i)No
(ii)No
(iii)Yes
(b) No
Explanation:
(a) The narrow sound pulse does not have a fixed wavelength or frequency. However, the speed of the sound pulse remains the same, which is equal to the speed of sound in that medium.
b) The short pip produced after every 20 s does not mean that the frequency of the whistle is`(1)/(20)` or 0.05 Hz. It means that 0.05 Hz is the frequency of the repetition of the pip of the whistle.
Promotional Banner

Topper's Solved these Questions

Similar Questions

Explore conceptually related problems

A narrow sound pulse (for example, short pip by a whistle ) is sent across a medium. (a) Does the pulse have a definite (i) wavelength (ii) frequency (iii) speed of propagation. (b) If the pulse rate is 1 after every 20s, i.e. the whistle is blown for a split second after every 20 second, is the frequency of the note produced by the whistle equal to 1//20=0.05Hz?

A narrow pulse (for example, a short pip by a whistle) is sent across a medium. If the pulse rate is 1 after every 20 s (that is the whistle is blow for a split of second after every 20 s). Is the frequency of the note produced by the whistle equal to 1//20 or 0.05 Hz ?

The engine of a train sound a whistle at frequency v, the frequency heard by a passenger is

An observer on a railway platform noticed that when a train passed through the station, at a speed of 72 kg h^(-1) , the frequency of the whistle appeared to drop by 500 Hz. Calculate the actual frequency of the note produced by the whistle. Velocity of sound in air = 340 ms^(-1) .

A: When a narrow pulse of light is sent through a medium, it doesn't retain its shape as it travels through the medium. R: Since the speed of propagation in a medium depends on wavelength , different wavelength components of the pulse travel with different speeds.

A train, blowing a whistle of frequency f, is standing in the railway yard A person is running towards the engine. The frequency of the sound of the whistle as heard by the person will be

A fire whistle emits a tone of 170 Hz. Take the speed of sound in air to be 340 m/s. The wavelength of this sound is about

NCERT-WAVES-EXERCISE
  1. A transverse harmonic wave on a strin is decribed by y(x,t) = 3.0 si...

    Text Solution

    |

  2. For the wave described in Exercise 15.8, plot the displacement (y) ver...

    Text Solution

    |

  3. For a travelling harmonic wave y=2.0 cos(10t-0.0080x+0.35), where x an...

    Text Solution

    |

  4. The transvers displacement of a string (clamped at its both ends) is g...

    Text Solution

    |

  5. (i) The transverse displacement of a string (clamped at its two ends )...

    Text Solution

    |

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

    Text Solution

    |

  7. A wire stretched between two rigid supports vibrates in its fundamenta...

    Text Solution

    |

  8. A metre-long tube open at one end, with a movable piston at the other ...

    Text Solution

    |

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

    Text Solution

    |

  10. A pipe 20cm long is closed at one end. Which harmonic mode of the pipe...

    Text Solution

    |

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

    Text Solution

    |

  12. Explain why (or how) : (a) In a sound wave, a displacement node is a p...

    Text Solution

    |

  13. A train, standing at the outer signal of a railway station blows a whi...

    Text Solution

    |

  14. A train, standing in a stationyard, blows a whistle of frequency 400Hz...

    Text Solution

    |

  15. A travelling harmonic wave on a string is described by y(x,t)=7.5sin(0...

    Text Solution

    |

  16. A narrow sound pulse (for example, a short pip by a whistle) is sent a...

    Text Solution

    |

  17. One end of a long string of linear mass dnesity 8.0xx10^(-3)kgm^(-1) i...

    Text Solution

    |

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

    Text Solution

    |

  19. Earthquakes generate sound waves inside the earth. Unlike a gas, the e...

    Text Solution

    |

  20. A bat is flitting about in a cave, navigating via ultrasonic beeps. As...

    Text Solution

    |