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# on gravity........ Watch

1. If we say sun has a gravitational pull larger then earth than why it does not attract slowly the atmosphere of earth towards it......?

well earth also holds it due to gravity...
Plz tell.....
2. Hi, I think, I'm not 100% sure, but isn't it to do with the formula F=(GMm)/r^2? Since r for the Sun and the Earth is 1.496x10^11m when you divide by this squared the force between then turns out to not be that much to cause that much of an effect.
Hopefully someone will correct me if I'm wrong but I think that may be it. Hope that helps 😄
3. (Original post by 1DA)
If we say sun has a gravitational pull larger then earth than why it does not attract slowly the atmosphere of earth towards it......?

well earth also holds it due to gravity...
Plz tell.....
The gravity from the Earth stops the atmosphere from being lost to space.

However the main reason it doesn't get pulled towards the Sun is that it's in orbit of the Sun. Because it has constant force at a right angle to the velocity, it moves around the Sun in a (rough) circle, so it never actually gets closer to the Sun.
4. well it is that ....
atmosphere is in orbit of earth but not in orbit of sun?

so it should be pulled...
5. Eh I think you'll learn this on As - gravity eqn. That's F=(GmM)/r^2 where gravity is inversely proportional to square of distance from their COM. Means gravity decreases as their distant from each other. You won't get pulled into the sun because you are much closer to earth than sun.
6. (Original post by 1DA)
well it is that ....
atmosphere is in orbit of earth but not in orbit of sun?

so it should be pulled...
It's in orbit of both.
7. (Original post by morgan8002)
It's in orbit of both.
I'm not sure whether the Earth's atmosphere would be considered in the Earth's orbit, considering that it actually touches the Earth. I think that the atmosphere is mostly kept up off the Earth's surface by the air pressure of the atmosphere below it.
8. (Original post by anosmianAcrimony)
I'm not sure whether the Earth's atmosphere would be considered in the Earth's orbit, considering that it actually touches the Earth. I think that the atmosphere is mostly kept up off the Earth's surface by the air pressure of the atmosphere below it.
True. I said that as a simplification. Its path around the Sun does have rotational cycles around the Earth.
9. Ahhh!!! Ok earths atmosphere is kept on earth because each particle is attracted to earth. If you consider it's attracted to the sun then sure, but earths gravitational influence to atmosphere is way more higher than that of sun(so resultant forces in air particles are towards earth)
10. but slowly and gradually sun should pull it as happens in the rope game..
as sun's gravity is not completely down till reaching earth?
11. (Original post by 1DA)
but slowly and gradually sun should pull it as happens in the rope game..
as sun's gravity is not completely down till reaching earth?
As I said, it is orbiting the Sun. You probably haven't covered circular motion if you're at GCSE, but if an object is moving and a force always acts perpendicular to the movement, it will move in a circle, ie. it won't move any closer to the Sun.

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