Home
Class 12
PHYSICS
Two express trains moving at 100 kilomet...

Two express trains moving at 100 kilometre per hour are travelling towards each other while one of them is whistling continuously. If the frequency of the note is 1000 Hz, find the apparent pitch to an observer in the other train (a) before the trains pass by each other and (b) after they have passed each other. (Velocity of sound in air `= 340 m//s`)

A

849 Hz before the trains pass by each other

B

1178 Hz , before the trains pass by each other

C

849 Hz, after the trains pass by each other

D

1178 Hz, after the trains pass by each other

Text Solution

Verified by Experts

The correct Answer is:
B, C
Promotional Banner

Topper's Solved these Questions

  • PHYSICS PART-III

    FIITJEE|Exercise ASSERTION -REASONING MCQ (SINGLE CORRECT)|12 Videos

  • PHYSICS PART-III

    FIITJEE|Exercise PARAGRAPH BASED (MULTIPLE CHOICE)|10 Videos

  • PHYSICS PART-III

    FIITJEE|Exercise ASSIGNMENT SECTION-II MCQ (SINGLE CORRECT)|47 Videos

  • OPTICS

    FIITJEE|Exercise NUMERICAL BASED QUESTIONS|2 Videos

  • PHYSICS PART2

    FIITJEE|Exercise Numerical Based Question Decimal Type|6 Videos

Similar Questions

Explore conceptually related problems

Two train travelling in opposite directions at 126 km/hr each, cross other while one of them is whistling if the frequency of the node is 2.22 kHz find the apparent frequency as head by an observer in the other train : (a) Before the trains cross each other (b) After the trains have crossed each other (V_("sound") = 335 m//sec)

Two trains A and B are approaching each other with 108 km h^(-1) and 126 km h^(-1) , respectively . If the train A sounds a whistle of frequency 500 Hz , find the frequency of the whistle as heard by a passenger in the train B . (a) before the trains cross each other and (b) after the trains cross each other . (Take velocity of sound as 330 m s^(-1) )

Two trains are moving towards each other at speeds of 72kmh^-1 and 54 kmh^-1 relative to the ground. The first train sounds a whistle of frequency 600 Hz. Find the frequency of the whistle as heard by a passenger in the second train a. before the trains meet and b. after teh trains have crossed each other. The speed of sound in air is 340 ms^-1

Two cars are moving towards each other with equal speed of 72 km h^(-1) . First car is emitting continuously a note of frequency 512 Hz. Find the apparent pitch heard by a person in 2^(nd) car before and after they cross each other. (Speed of sound = 340 m/s)

Two aeroplanes are moving towards each other. One of them blows a horn the person in the other plane hears the sound. The apparent pitch will

Two trains, each having a speed of 30 km//h , are headed towards each other

Two passenger trains moving with a speed of 108km//hour cross each other. One of them blows a whistle whose frequency is 750Hz . If sound speed is 330m//s , then passengers sitting in the other train, after trains cross each other will hear sound whose frequency will be

Two trains are travelling towards each other both at a speed of 90 km h^-1 . If one of the trains sounds a whistle at 500 Hz, what will be the apparent frequency heard in the other train ? Speed of sound in air = 350 m s^-1.

Two trains are moving towards each other and cross each other. The apparent pitch

Two trains, each moving with a velocity of 30 ms^-1 , cross each other. One of the trains gives a whistle whose frequency is 600 Hz. If the speed of sound is 330 ms^-1 , the apparent frequency for passengers sitting in the other train before crossing would be

FIITJEE-PHYSICS PART-III-MCQ (MULTIPLE CORRECT)
  1. In equation varepsilon =A sin (omegat-kx) where t is in second and x i...

    Text Solution

    |

  2. Choose the correct alternative (s) from the following .

    Text Solution

    |

  3. A simple pendulum has a bob of mass m and swings with an angular ampli...

    Text Solution

    |

  4. A metallic wire of diameter 0.3 mm and length 3m is stretched by hangi...

    Text Solution

    |

  5. The transverse displacement of a string clamped at its both ends is gi...

    Text Solution

    |

  6. Two express trains moving at 100 kilometre per hour are travelling tow...

    Text Solution

    |

  7. A satellite is projected horizontally (parallel to the tangent on equa...

    Text Solution

    |

  8. Which relations are always correct in between the displacement (vecx) ...

    Text Solution

    |

  9. if each cm of main scale is divided in q equal parts and p vernier sca...

    Text Solution

    |

  10. A particle moves along the x-axis according to the equation x=a sin ...

    Text Solution

    |

  11. Choose the correct statement regarding X-ray .

    Text Solution

    |

  12. During beta-decay of stationary nucleus , an electron is observed with...

    Text Solution

    |

  13. A thin glass plate of thickness t(=lambda//3,lambda being the waveleng...

    Text Solution

    |

  14. Sounds from two identical sources S(1) and S(2) reach a point P. When ...

    Text Solution

    |

  15. A vibrating string produces 2 beats per secod when sounded with a turn...

    Text Solution

    |

  16. When the nucleus of an electrically neutral atom undergoes a radioacti...

    Text Solution

    |

  17. Which of the following assertions are correct ?

    Text Solution

    |

  18. Whenever a hydrogen atom emits a photon in the Balmer series ,

    Text Solution

    |