Home
Class 7
PHYSICS
John places an alarm clock inside a box ...

John places an alarm clock inside a box as shown in the given figure. He then creates a vacuum inside the box. When the alarm goes on, John does not hear the alarm-sound.
John does not hear the alarm sound because

A

the walls of the box block the sound

B

sound cannot travel through vacuum

C

there is no medium between John and the box

D

the inside wall of the box reflects the sound back

Text Solution

AI Generated Solution

Promotional Banner

Topper's Solved these Questions

  • SOUND

    BEIITIANS|Exercise IIT JEE Worksheet (I. Single Correct Answer Type)|10 Videos

  • SOUND

    BEIITIANS|Exercise IIT JEE Worksheet (II. Multiple Correct Answer Type)|5 Videos

  • SOUND

    BEIITIANS|Exercise Summative Worksheet |10 Videos

  • MOTION

    BEIITIANS|Exercise IIT JEE WORKSHEET (MATIRX MATCHING) |1 Videos

  • WIND, STROM AND CYCLONES

    BEIITIANS|Exercise IIT JEE Worksheet (II. Multiple Correct Answer Type)|1 Videos

Similar Questions

Explore conceptually related problems

There is a hollow glass partition in a room. It divides the room in two compartments. Two brothers X and Y are sitting in each compartment. An alarm clock, which is placed inside the glass partition, is producing sound, as shown in the given figure. Both brothers are able to hear the sound. All the air from within the glass partition is removed with the help of a vacuum pump. After evacuating the partition completely,

An electric drum is enclosed inside a specially designed closed glass chamber, as shown in the given figure. On switching the current, the hammer repeatedly strikes the membrane of the drum. Hence, the membrane vibrates and produces sound that can be heard at a distance. Now, the chamber is evacuated by closing the switch of the vacuum pump. As the chamber is evacuated, the

A large , heavy box is sliding without friction down a smooth plane of inclination theta . From a point P on the bottom of the box , a particle is projected inside the box . The initial speed of the particle with respect to the box is u , and the direction of projection makes an angle alpha with the bottom as shown in Figure . (a) Find the distance along the bottom of the box between the point of projection p and the point Q where the particle lands . ( Assume that the particle does not hit any other surface of the box . Neglect air resistance .) (b) If the horizontal displacement of the particle as seen by an observer on the ground is zero , find the speed of the box with respect to the ground at the instant when particle was projected .

Three boys Ravi, John and Asif stand in a straight line as shown in figure. Ravi and Asif fire crackers at the same instant of time. John hears the first sound after 2 s and the second sound after 2.5 s. Determine the distance between Ravi and Asif. The velocity of sound in air is 330 ms^(-1) .

A man stationed between two parallel cliffs fires a gun. He hears the first echo after 1.5 s and the next after 2.5 s . What is the distance between the cliffs and when does the hear the third echo ? Take the speed of sound in air as 340 m//s .

When a sound wave enters the ear, it sets the eardrum into oscillation, which in turn causes oscillation of 3 tiny bones in the middle ear called ossicles. This oscillation is finally transmitted to the fluid filled in inner portion of the ear termed as inner ear, the motion of the fluid disturbs hair cells within the inner ear which transmit nerve impulses to the brain with the information that a sound is present. The theree bones present in the middle ear are named as hammer, anvil and stirrup. Out of these the stirrup is the smallest one and this only connects the middle ear to inner ear as shown in the figure below. The area of stirrup and its extent of connection with the inner ear limits the sensitivity of the human ear consider a person's ear whose moving part of the eardrum has an area of about 50mm^2 and the area of stirrup is about 5mm^2 . The mass of ossicles is negligible. As a result, force exerted by sound wave in air on eardum and ossicles is same as the force exerted by ossicles on the inner ear. Consider a sound wave having maximum pressure fluctuation of 4xx10^-2Pa from its normal equilibrium pressure value which is equal to 10^5Pa . Frequency of sound wave in air is 332(m)/(s) . Velocity of sound wave in fluid (present in inner ear) is 1500(m)/(s) . Bulk modulus of air is 1.42xx10^5Pa . Bulk modulus of fluid is 2.18xx10^9Pa . Q. This person (without hearing aid machine) is sitting inside a busy restaurant where average sound intensity is 3.2xx10^-5(W)/(m^2) . How much energy in the form of sound is taken up by the person in his meal time of 1 h?

When a sound wave enters the ear, it sets the eardrum into oscillation, which in turn causes oscillation of 3 tiny bones in the middle ear called ossicles. This oscillation is finally transmitted to the fluid filled in inner portion of the ear termed as inner ear, the motion of the fluid disturbs hair cells within the inner ear which transmit nerve impulses to the brain with the information that a sound is present. The theree bones present in the middle ear are named as hammer, anvil and stirrup. Out of these the stirrup is the smallest one and this only connects the middle ear to inner ear as shown in the figure below. The area of stirrup and its extent of connection with the inner ear limits the sensitivity of the human ear consider a person's ear whose moving part of the eardrum has an area of about 50mm^2 and the area of stirrup is about 5mm^2 . The mass of ossicles is negligible. As a result, force exerted by sound wave in air on eardum and ossicles is same as the force exerted by ossicles on the inner ear. Consider a sound wave having maximum pressure fluctuation of 4xx10^-2Pa from its normal equilibrium pressure value which is equal to 10^5Pa . Frequency of sound wave in air is 332(m)/(s) . Velocity of sound wave in fluid (present in inner ear) is 1500(m)/(s) . Bulk modulus of air is 1.42xx10^5Pa . Bulk modulus of fluid is 2.18xx10^9Pa . Q. If the person is using an hearing aid, which increase the intensity of given sound wave change as perceived by inner ear?

A closed cubical box of negligible mass has large number of spherical balls arranged neatly inside it as shown in the figure. When placed in water, the box floats with 80% of its volume remaining. Submerged. What is specifc gravity of material of the balls? Neglect thickness of the wall of the box.

BEIITIANS-SOUND-HOTS Worksheet
  1. John places an alarm clock inside a box as shown in the given figure. ...

    Text Solution

    |

  2. Which part of a tabla vibrates to produce sound?

    Text Solution

    |

  3. Which of the following effects cannot be produced by a force?

    Text Solution

    |

  4. Hearing impiarment is caused by either excessive noise or injury, dise...

    Text Solution

    |

  5. Jackhammer is an electric device that is used to drill on hard surface...

    Text Solution

    |

  6. In medical sciences, doctors use ultrasound devices to investigate and...

    Text Solution

    |

  7. Jackhammer is an electric device that is mainly used for drilling on a...

    Text Solution

    |

  8. Telephone operators answer the calls on telephones. A sound is easily ...

    Text Solution

    |

  9. Humans are able to hear because of the vibration of a stretched thin m...

    Text Solution

    |

  10. There is a hollow glass partition in a room. It divides the room in tw...

    Text Solution

    |

  11. An electric drum is enclosed inside a specially designed closed glass ...

    Text Solution

    |

  12. Dolphins and whales communicate under water using sound. They can see ...

    Text Solution

    |

  13. Microphone is an electrical device that is used to amplify a human voi...

    Text Solution

    |

  14. Astronauts in deep space use radio devices to communicate with each ot...

    Text Solution

    |

  15. Underwater detection of objects is possible in navigation because

    Text Solution

    |

  16. Astronauts use walkie-talkie to communicate to each other in deep spac...

    Text Solution

    |

  17. When stretched thread is plucked, it starts a vibrating. The given inf...

    Text Solution

    |

  18. The presence of excessive and the surroundings may cause

    Text Solution

    |

  19. Which of the following preventive measures cannot be attributed to roa...

    Text Solution

    |