Home
Class 12
PHYSICS
Determine the speed with which the earth...

Determine the speed with which the earth would have to rotate on its axis , so that a person on the equator would weigh `(3)/(5)` th as much as the person. Take `R = 6400 km`.

Text Solution

Verified by Experts

Weight on the equator `W'=3/5 W implies 3/5 mg = mg - momega^(2) R" "implies" "omega = sqrt((2g)/(5R))`.
Promotional Banner

Topper's Solved these Questions

  • GRAVITATION

    ALLEN |Exercise BOX-1|3 Videos

  • GRAVITATION

    ALLEN |Exercise BOX-2|13 Videos

  • GRAVITATION

    ALLEN |Exercise Exercise 5 B (Previous Year Questions)|9 Videos

  • GEOMETRICAL OPTICS

    ALLEN |Exercise subjective|14 Videos

  • KINEMATICS-2D

    ALLEN |Exercise Exercise (O-2)|47 Videos

Similar Questions

Explore conceptually related problems

If the speed of rotation of earth about its axis increases, then the weight of the body at the equator will

What would be the angular speed of earth, so that body lying on equator may appear weightless? ( g = 10 m//s^2 , radius of earth = 6400 km)

The earth takes 24 h to rotate once about its axis. How much time does the sun take to shift by IS when viewed from the earth ?

The earth takes 24 h to rotate once about its axis. How much time does the sun take to shift by 1° when viewed from the earth?

A satellite is to be placed in equatorial geostationary orbit around the earth for communication. (a) Calculate height of such a satellite. (b) Find out the minimum number of satellites that are needed to cover entire earth, so that atleast one satellite is visible from any point on the equator. [M = 6 xx 10^(24) kg, R = 6400 km, T = 24 h, G = 667 x 10-^(11) SI unit]

The total number of ways in which 5 balls of differert colours can be distributed among 3 persons so thai each person gets at least one ball is

The principle of 'parallax' in section 2.3.1 is used in the determination of distances of very distant starts. The baseline AB is the line joining the Earth's two locations six months apart in its orbit around the Sun. That is, the baseline is about the diameter of the Earth's orbit = 3xx10^(11)m . However, even the nearest stars are so distant that with such a long baseline, they show parallax only of the order of 1" (second) of arc or so. A parsec is a conventent unit of length on the astronomical scale. It is the distance of an object that will show a parallax of 1" (second of arc) from opposite ends of a baseline equal to the distance from the Earth to the Sun. How much is a parsec in terms of metres ?

A 100 turn closely wound circular coil of radius 10 cm carries a current of 3.2 A. (a) What is the field at the centre of the coil? (b) What is the magnetic moment of this coil? The coil is placed in a vertical plane and is free to rotate about a horizontal axis which coincides with its diameter. A uniform magnetic field of 2T in the horizontal direction exists such that initially the axis of the coil is in the direction of the field. The coil rotates through an angle of 90^@ under the influence of the magnetic field. (c) What are the magnitudes of the torques on the coil in the initial and final position? (d) What is the angular speed acquired by the coil when it has rotated by 90^@ ? The moment of inertia of the coil is 0.1 kg m^2 .

ALLEN -GRAVITATION-Illustration
  1. Which of the following statement are true about acceleration due to gr...

    Text Solution

    |

  2. At what height above the earth's surface the acceleration due to gravi...

    Text Solution

    |

  3. Determine the speed with which the earth would have to rotate on its a...

    Text Solution

    |

  4. Draw a rough sketch of the variation in weight of a spacecraft which m...

    Text Solution

    |

  5. A solid sphere of uniform density and radius R applies a gravitational...

    Text Solution

    |

  6. The maximum vertical distance through which an astronaut can jump on t...

    Text Solution

    |

  7. Three solid sphere of mass M and radius R are placed in contact as sho...

    Text Solution

    |

  8. Four bodies each of mass m are placed at the different corners of a sq...

    Text Solution

    |

  9. A body of mass m is placed on the surface of earth. Find work required...

    Text Solution

    |

  10. if velocity given to an object from the surface of the earth is n time...

    Text Solution

    |

  11. a narrow tunnel is dug along the diameter of the earth, and a particle...

    Text Solution

    |

  12. The escape velocity for a planet is v(e), A particle starts from rest ...

    Text Solution

    |

  13. A particle is projected vertically upwards the surface of the earth (r...

    Text Solution

    |

  14. A mass of 6xx10^24 kg (equal to the mass of the earth) is to be compre...

    Text Solution

    |

  15. Gravitational potential difference between a point on surface of plane...

    Text Solution

    |

  16. A body of mass m kg starts falling from a distance 2R above the earth'...

    Text Solution

    |

  17. With what velocity must a body be thrown from earth's surface so that ...

    Text Solution

    |

  18. Two satellites S(1) and S(2) are revolving round a planet in coplanar ...

    Text Solution

    |

  19. A space-ship is launched into a circular orbit close to ther earth's s...

    Text Solution

    |

  20. A astronaut inside an earth satellite experiences weightlessness becau...

    Text Solution

    |