Home
Class 12
PHYSICS
A barometer kept in an elevator accelera...

A barometer kept in an elevator accelerating upward reads 76 cm. The air pressure in the elevator is

A

76 cm

B

`lt76 cm`

C

`gt76 cm`

D

zero

Text Solution

Verified by Experts

Promotional Banner

Topper's Solved these Questions

  • MECHANICAL PROPERTIES OF FLUIDS

    CHETANA PUBLICATION|Exercise Exercise|91 Videos

  • Magnetic Materials

    CHETANA PUBLICATION|Exercise EXERCISE|74 Videos

  • Oscillations.

    CHETANA PUBLICATION|Exercise EXERCISE|69 Videos

Similar Questions

Explore conceptually related problems

A man of mass 80 kg stands in an elevator. Calculate his apparent weight when, (ii) elevator is uniformly accelerated upwards at 2 m//s^2

A simple pendulum of length 1 m is freely suspended from the ceiling of an elevator. The time period of small oscillations as the elevator moves up with an acceleration of 2m//s^2 is (use g=10 m//s^2 )

A metal block of mass 10 kg is kept on a table. If the contact surface area is 100 cm^2 . Find the pressure on the table.

In car lift compressed air exerts a force F_1 on a small piston having a radius of 5 cm. This pressure is transmitted to a second piston of radius 15 cm. If the mass of the car to be lifted is 1350 kg, what is F_1 ? What is the pressure necessary to ac complish this task ?

A barometer tube of length 90 cm contains some air above mercury. The reading of the mercury level is 74.8 cm when the atmospheric pressure is 76 cm and temperature is 30^@C . If the reading is observed to be 75.4 cm on some another day when temperature is 10^@C , then what will be true pressure?

A particle is kept fixed on a turn table rotating uniformly. As seen from the ground , the particle goes in a circle , its speed is 20 cm/s and acceleration 20 cm/s^2 . The particle is now shifted to make radius half of the original value. The new values of speed and acceleration will be

A soap bubble of diameter 6mm is formed in air . The surface tension of liquid is 30 dyne/cm . The excess pressure inside the soap bubble is

A person of mass 60 kg stands on a weighing scale in a lift (elevator). What would the scale read if the elevator moves (i) up with a uniform speed of 5 m//s (ii) down with a uniform acceleration of 4 m//s^2 (iii) up with a uniform acceleration of 4 m//s^2 ? [Given : g = 10 m//s^2 ]

Two soap bubbles A and B are kept in a closed chamber where the air is maintained at pressure 8 N//m^(2) . The radii of bubbles A and B are 2 cm and 4 cm , respectively. Surface tension of the soap. Water used to make bubbles is 0.04 N//m . Find the ratio n_(B)//n_(A) , where n_(A) and n_(B) are the number of moles of air in bubbles A and B respectively. [Neglect the effect of gravity.]

A particle is projected obliquely into air with velocity of 20 m/s at an angle of elevation of 45^@ . Neglecting air resistance the equation of motion is

CHETANA PUBLICATION-MECHANICAL PROPERTIES OF FLUIDS-Exercise
  1. If Reynold's number for given ideal fluid flowing in the tube is 750, ...

    Text Solution

    |

  2. If pressure at half the depth of a lake is equal to 2/3 pressure at th...

    Text Solution

    |

  3. A barometer kept in an elevator accelerating upward reads 76 cm. The a...

    Text Solution

    |

  4. There is a hole in the bottom of a tank having water. If total pressur...

    Text Solution

    |

  5. Water falls from a tap, down the streamline

    Text Solution

    |

  6. The working of an atomizer depends upon

    Text Solution

    |

  7. By sucking through a straw, a student can reduce the pressure in his l...

    Text Solution

    |

  8. The relative velocity between two layers of fluid, separated by 0.4 mm...

    Text Solution

    |

  9. Pascal's law is applied in which of the following cases?

    Text Solution

    |

  10. Select and write the correct answer:- The energy stored in a soap bubb...

    Text Solution

    |

  11. Select and write the correct answer:- Two capillary tubes of radii 0.1...

    Text Solution

    |

  12. The dimensions of surface tension are

    Text Solution

    |

  13. Water falls from a tap, down the streamline

    Text Solution

    |

  14. State and explain Pascal 's law.

    Text Solution

    |

  15. What is an incompressible fluid ?

    Text Solution

    |

  16. How much amount of work is done in forming a soap bubble of radius r?

    Text Solution

    |

  17. Why is the surface tension of paints and lubricating oils kept low ?

    Text Solution

    |

  18. Why does velocity increase when water flowing in broader pipe enters a...

    Text Solution

    |

  19. Define surface tension. Write down its units and dimension.

    Text Solution

    |

  20. Find the pressure 200 m below the surface of the ocean if pressure on ...

    Text Solution

    |