While reading gravitation chapter I

In summary: Earth in the same reference frame as the Earth is falling towards the apple, but the apple's inertial frame is Accelerating so the pseudo force is bigger)
  • #1
Alche
21
0
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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  • #2


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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  • #3


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. :)
 
  • #4


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
 
  • #5


1) The weight of the Earth refers to the gravitational force exerted by the Earth on an object due to its mass. This force is responsible for keeping objects on the Earth's surface and is also responsible for the Earth's orbit around the sun.

2) The weight of an object as measured by a spring balance does not change throughout the day. This is because the force of gravity between the object and the Earth remains constant regardless of the position of the sun.

3) The force needed to accelerate the Earth with an acceleration of g is exerted by the Earth itself. This is due to the principle of action and reaction, where every action has an equal and opposite reaction.

4) Yes, the nut will eventually land on the Earth due to the Earth's gravitational pull. Its landing spot will depend on its trajectory and the Earth's rotation. An astronaut could potentially use a thruster to change the nut's trajectory and make it land at a desired location on Earth.

5) No, the plane of orbit of a satellite does not need to pass through the center of the Earth. As long as the satellite is in a stable orbit and maintains a certain distance from the Earth, it will continue to orbit without passing through the center.

6) The person at the equator does not feel weightless because they are still within the Earth's gravitational field. The force of gravity is still acting on them, but it is balanced by the centrifugal force caused by the rotation of the Earth. In contrast, a satellite is outside of the Earth's atmosphere and is not subject to the same forces, causing the sensation of weightlessness.
 

1. What is gravitation?

Gravitation is the force of attraction between two objects with mass. It is responsible for the movement of planets, stars, and other celestial bodies in the universe.

2. Who discovered the concept of gravitation?

The concept of gravitation was first discovered by Sir Isaac Newton in 1687. He published his theory of gravity in his famous book "Philosophiæ Naturalis Principia Mathematica".

3. How does gravitation affect the Earth?

Gravitation affects the Earth by keeping it in orbit around the Sun and maintaining the Moon's orbit around the Earth. It also causes objects to fall towards the Earth's surface and is responsible for the Earth's shape and rotation.

4. What is the difference between mass and weight in terms of gravitation?

Mass is a measure of the amount of matter in an object, while weight is a measure of the force of gravity acting on an object. In other words, mass is constant, but weight can vary depending on the strength of the gravitational force.

5. How is the strength of gravitation calculated?

The strength of gravitation is calculated using Newton's law of gravitation, which states that the force of gravity between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

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