While reading gravitation chapter I

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Discussion Overview

The discussion revolves around various concepts related to gravitation, including the meaning of the "weight of the Earth," the effects of gravitational forces at different times of the day, the behavior of objects detached from satellites, and the experiences of individuals on the Earth's surface in relation to gravitational forces. The scope includes theoretical questions and conceptual clarifications regarding gravitational interactions.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question the meaning of the "weight of the Earth" and suggest it may vary based on the mass of objects exerting gravitational force on it.
  • There is a query about whether the weight of an object on Earth's surface is greater at midnight compared to noon due to the alignment of gravitational forces from the Sun and Earth.
  • One participant raises a hypothetical scenario about an apple falling and questions the source of the force that accelerates the Earth towards the apple, introducing the concept of a pseudo force in a frame of reference.
  • The fate of a nut detached from a satellite is discussed, with one participant suggesting that its landing on Earth depends on its location relative to the satellite and the gravitational forces acting on it.
  • A question is posed regarding the necessity of a satellite's orbital plane passing through the center of the Earth.
  • Another participant inquires why a person at the equator does not experience weightlessness despite moving in a circular path similar to a satellite.

Areas of Agreement / Disagreement

Participants express various viewpoints and questions without reaching consensus on the discussed topics. Multiple competing views remain, particularly regarding the implications of gravitational forces and the behavior of objects in different scenarios.

Contextual Notes

Some claims depend on specific assumptions about gravitational interactions and frames of reference, which are not fully resolved in the discussion.

Alche
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While reading gravitation chapter I got some doubts, and that I am posting here.

1) Is there any meaning of "Weight of the Earth"?


2)At noon, the sun and the Earth pull the objects on the Earth's surface in opposite direction. At midnight the sun and the Earth pull these objects in the same direction. Is the weight of an object as measured by the spring balance on the Earth's surface more at midnight as compared to its weight at noon?

3)An apple falls from a tree. An insect in the apple finds that the Earth is falling towards it with an acceleration g. Who exerts the force needed to accelerate the Earth with this acceleration g?

4)A nut becomes loose and gets detached from a satellite revolving around the earth. Will it land on earth? If yes then where? If no, how can an astronaut make it land on the earth?

5)Is it necessary for the plane of the orbit of a satellite to pass through the centre of the earth?

6)As Earth rotates about its axis, a person living in his house at the equator goes in a circular obit of radius equal to the radius of the earth. Why does he/she not feel weightlessness as a satellite passenger feels?
 
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Alche said:
While reading gravitation chapter I got some doubts, and that I am posting here.

1) Is there any meaning of "Weight of the Earth"?

I think it has, but it will be different for different planets and stars since they have different masses, so they'll be attracting Earth towards themselves with different magnitude of force because,

g(acceleration due to gravity) = √GM/R2, where M & R are the mass and the radius of the body that is attracting Earth towards itself and

weight of Earth will differ man-to-man

for a man of mass 50 kg, weight of Earth is 50g N for a man of weight 60kg weight of Earth is 60g N (if weight is force with which the man attracts the Earth toward's his centre of gravity
 
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Alche said:
4)A nut becomes loose and gets detached from a satellite revolving around the earth. Will it land on earth? If yes then where? If no, how can an astronaut make it land on the earth? .

Well the nut will land or not on the Earth depends on where it is located, it will surely land on the Earth if its inside the satellite( yeah I agree that, for that satellite too has to land on the earth). It is also depended on where satellite is located, if it is located far away from the Earth and the nut is out side it and where the gravitational force is only optimum may be then nut will fly off in the space.

Don't know how will astronaut will make it land on earth. :P:P So please help. :)
 


Alche said:
3)An apple falls from a tree. An insect in the apple finds that the Earth is falling towards it with an acceleration g. Who exerts the force needed to accelerate the Earth with this acceleration g?

frame-of-reference!

the force exerted is the pseudo force
 

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