Home
Class 12
PHYSICS
A man stands at rest in front of a large...

A man stands at rest in front of a large smooth wall. Directly in front of him, between him and the wall he holds a vibrating tuning fork of frequency 400Hz. He now moves the fork towards the wall with a speed of 1m/s. How many beats/s will he hear between the sound waves reaching him directly from the fork, and those reaching him after being reflected from the wall ?

A

`1 . 15 beats //s`

B

`2 . 30 beats //s`

C

`4 . 60 beats //s`

D

`9 . 20 beats //s`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • SOUND WAVES

    MOTION|Exercise Exercise - 3 (Section - A)|27 Videos

  • SOUND WAVES

    MOTION|Exercise Exercise - 3 (Section - B)|14 Videos

  • SOUND WAVES

    MOTION|Exercise Exercise - 1|82 Videos

  • SIMPLE HARONIC MOTION

    MOTION|Exercise EXERCISE -4 (Leve-II) [ JEE 2011]|11 Videos

  • SURFACE TENSION

    MOTION|Exercise Exercise - 3 | Section - B Previous Year Problems | AIEEE|12 Videos

Similar Questions

Explore conceptually related problems

A car, sounding a horn of frequency 1000 Hz, is moving directly towards a huge wall at a speed of 15 m/s. If speed of sound is 340 m/s, then the frequency of the echo heard by the driver is

A man holding a tuning fork of frequency 90 hertz runs straight towards a stationary wall with velocity of 3.7 m/sec. The number of beats per second heard by him is (Speed of sound in air =340m/s.)

A tuning fork 'P' of frequency 280Hz produces 6 beats/s with unknown tuning fork 'Q'

A tuning fork of frequency 328Hz is moved towards a wall at a speed of 2ms^(-1) . An observer standing on the same side as the fork hears two sounds, one directly from the fork and the other reflected from the wall. Number of beats per second is (Velocity of sound in air 330ms^(-1) ).

A car moves with a speed of 54 kmh^-1 towards a cliff. The horn of the car emits sound of frequency 400 Hz at a speed of 335 m s^-1 . (a) Find the wavelength of the sound emitted by the horn in front of the car. (b) Find the wavelength of the wave reflected from the cliff (c) What frequency does a person sitting in the car hear for the reflected sound wave ? (d) How many beats does he hear in 10 seconds between the sound coming directly from the horn and that coming after the reflection ?

A man is running with a fork of frequency 340 Hz towards a huge wall with a velocity 2m/s, then the number of beats heard per second is (Velocity of sound in air is 342 m/s)

A car blowing a horn of frequency 350 Hz is moving normally towards a wall a speed of 5 m/s The beat frequency heard by a person standing between the car and wall is (speed of sound in air =350 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) )

If a tuning fork of frequency 512Hz is sounded with a vibrating string of frequency 505.5Hz the beats produced per sec will be

A tuning fork of frequency 380 Hz is moving towards a wall with a velocity of 4(m)/(s) Then the number of beats heard by a stationary listener between direct and reflected sound will be (velocity of sound in air is 340(m)/(s) )

MOTION-SOUND WAVES-Exercise - 2
  1. The sun is rotating about its own axis. The spectral lines imitted fro...

    Text Solution

    |

  2. An observer moving towards a stationary source observes that the appar...

    Text Solution

    |

  3. If the velocity of sound is V, velocity of the observer is V(0) and ...

    Text Solution

    |

  4. When a source of frequency n is receding away from a stationary observ...

    Text Solution

    |

  5. A source is approaching a stationary observer with uniform acceleratio...

    Text Solution

    |

  6. A star, emitting green light, is approaching the earth with uniform ac...

    Text Solution

    |

  7. A man stands at rest in front of a large smooth wall. Directly in fron...

    Text Solution

    |

  8. A whistle is rotated with 2 rotations/sec in a circle of radius 1 mete...

    Text Solution

    |

  9. {:(overset(*)(A),overset(*)(S(1)),overset(*)(B),overset(*)(S(2)),overs...

    Text Solution

    |

  10. A person is standing at distance of r from a source of sound. The freq...

    Text Solution

    |

  11. If the wavelength of light emitted by a star is shifted towards red en...

    Text Solution

    |

  12. Two whistles Aand B produces notes of frequencies 660 Hz and 596 Hz re...

    Text Solution

    |

  13. The frequency of a radar is 780 MHz. After getting reflected from an a...

    Text Solution

    |

  14. If a source sounding a whistle with a constant frequency moves in a ci...

    Text Solution

    |

  15. A band playing music at a frequency f is moving towards a wall at a sp...

    Text Solution

    |

  16. An engine giving whistle is moving towards a stationary observer with ...

    Text Solution

    |

  17. Velocity of sound in air is 332 m//sec . The shortest length of an ope...

    Text Solution

    |

  18. two sound sources are moving in oppostive directions with velocities ...

    Text Solution

    |

  19. engine as heard by an observer, when the engine moves towards the obse...

    Text Solution

    |

  20. A car moving at 20 m//s with its horn blowing (n = 1200 Hz) is chasing...

    Text Solution

    |