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avito009
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Why does the Earth not fall into the sun? Is it because Earth has angular momentum? or is it because the Earth has orbital momentum?
why angular momentum.The moon is tidal locked so no angular momentum is applied. I believe that the moon get pulled in and swings out to the other side and get further away and repeats. Picture this, a cut rubber band attached to a tennis ball and swing it over your head. The rubber band acts like the gravity while the tennis is the moon and the hand is the earth.You see, the moon did not get pulled in by the rubber band but as it pulls in, it moves forward and continue to fall away from the Earth but the Earth grab it and so on and so on.Orbital motion i think is the reason. Correct me if i am wrong as it is my observation.Drakkith said:Both. It has angular momentum about an axis passing through the Sun due to its orbital motion. You could call this orbital angular momentum. It also spins around its own axis, but that is unrelated to its orbital motion.
Interesting, but a few small details could be refined.Neon said:why angular momentum.The moon is tidal locked so no angular momentum is applied. I believe that the moon get pulled in and swings out to the other side and get further away and repeats. Picture this, a cut rubber band attached to a tennis ball and swing it over your head. The rubber band acts like the gravity while the tennis is the moon and the hand is the earth.You see, the moon did not get pulled in by the rubber band but as it pulls in, it moves forward and continue to fall away from the Earth but the Earth grab it and so on and so on.Orbital motion i think is the reason. Correct me if i am wrong as it is my observation.
Neon said:why angular momentum.The moon is tidal locked so no angular momentum is applied.
The moon rotates around its axis. Anything that rotates around its center of mass has angular momentumNeon said:why angular momentum.The moon is tidal locked so no angular momentum is applied.
Nothing else acts like gravity.256bits said:The rubber band does have a tension force when stretched, and the force will increase with more of the more the stretch.
Gravity on the other hand decreases with distance. Gravity is entirely not like a rubber band.
Neon said:Nothing else acts like gravity.
There is no reason why you couldn't make a device that would follow ISL for force / extension. It would be very possible if the device had 'active' control (power supplied from the central pivot) . Of course, it would not be 'elastic' but that wouldn't matter if you just wanted to produce an elliptical orbit with it. Come to think of it. I'm surprised I haven't seen this at some Science Exhibition; they all seem to make do with the conventional tapered bowl with balls orbiting round.Neon said:string does not act like gravity because well you should know.Basically nothing that is elastic and the tension gets weaker the more it gets pulled.
Let us suppose the moon did not rotate around it's own axis even though from Earth it would look like it does.This property would not cause the moon to fall into the Earth any more than the Earth would fall into the sun if it behaved in a similar manner.phinds said:The moon rotates around its axis. Anything that rotates around its center of mass has angular momentum
The fact that the Moon and Earth are not homogenious spheres means that the angular momentum of each of them becomes relevant. The tidal effects between the two is causing the angular momentum of their individual rotations to be coupled to the angular orbital momentum. The effect is that the Moon's orbit around the Earth is very slowly increasing in radius. So you cannot completely separate the rotational and orbital momenta.Buckleymanor said:Let us suppose the moon did not rotate around it's own axis even though from Earth it would look like it does.This property would not cause the moon to fall into the Earth any more than the Earth would fall into the sun if it behaved in a similar manner.
It is the orbital rotation of the Earth around the sun irrespective of it's angular momentum about it's own axis which stops it falling into the sun.
I agree but as far as the op is concerned it's about a decrease in radius rather than an increase.sophiecentaur said:The fact that the Moon and Earth are not homogenious spheres means that the angular momentum of each of them becomes relevant. The tidal effects between the two is causing the angular momentum of their individual rotations to be coupled to the angular orbital momentum. The effect is that the Moon's orbit around the Earth is very slowly increasing in radius. So you cannot completely separate the rotational and orbital momenta.
I was simply responding to the issue of whether or not the moon has angular momentum. Do you argue that it does not? I was not addressing anything about orbits.Buckleymanor said:Let us suppose the moon did not rotate around it's own axis even though from Earth it would look like it does.This property would not cause the moon to fall into the Earth any more than the Earth would fall into the sun if it behaved in a similar manner.
It is the orbital rotation of the Earth around the sun irrespective of it's angular momentum about it's own axis which stops it falling into the sun.
Ask your self this: How could it?avito009 said:Why does the Earth not fall into the sun? Is it because Earth has angular momentum? or is it because the Earth has orbital momentum?
Obviously from my reply I regard it does have angular momentum .Mt reply was just an attempt to bring the thread back on topic as far as all the op questions.phinds said:I was simply responding to the issue of whether or not the moon has angular momentum. Do you argue that it does not? I was not addressing anything about orbits.
the Earth is falling into the sun - but it is falling in a straight line in curved space so it never gets there - try imaging it from the side you would see a corkscrew pathavito009 said:Why does the Earth not fall into the sun? Is it because Earth has angular momentum? or is it because the Earth has orbital momentum?
If the Earth suddenly stopped spinning, the atmosphere would continue to rotate at the same speed, causing winds of over 1,000 miles per hour. This would result in devastating storms and hurricanes. Additionally, the change in rotation would affect the Earth's magnetic field, leading to disruptions in communication and navigation systems.
No, the Earth's gravity would not change if it stopped spinning. Gravity is determined by the mass of an object, and the rotation of the Earth does not affect its mass. However, the change in rotation could impact the Earth's shape and size, potentially altering the gravitational pull in certain areas.
If the Earth stopped spinning, the temperature would vary greatly between the light and dark sides of the planet. The side facing the Sun would experience extreme heat, while the side facing away from the Sun would become extremely cold. This could potentially lead to the extinction of many plant and animal species.
No, there would not be day and night if the Earth stopped spinning. The rotation of the Earth on its axis is what causes the cycle of day and night. Without this rotation, one side of the Earth would always face the Sun, while the other side would always face away from it.
No, it is not possible for the Earth to completely stop spinning. The Earth's rotation is caused by its initial momentum and the gravitational pull of the Sun and Moon. While the Earth's rotation may slow down or speed up slightly over time, it will never come to a complete stop.