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James Gordon
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If gravity pulls things towards an object, is it possible that gravity pulls the object itself towards its own center, creating inertia?
James Gordon said:If gravity pulls things towards an object, is it possible that gravity pulls the object itself towards its own center, creating inertia?
Nugatory said:No.
James Gordon said:Is there a particular concept in physics that would help me to understand why?
Nugatory said:If you want to know how gravity behaves, classical Newtonian mechanics works well, and there are many excellent texts.
If you want to understand the current level of understanding of what gravity is and how it relates to mass and inertia, you'll have to spend some time learning what general relativity is about. There are s many bad pop-sci explanations out there that I'm reluctant to recommend a google search, but if you search through the relativity forum here you'll find some good answers (I particularly recommend member A.T.'s short video about an apple hanging on a branch and then falling) and also some good book recommendations.
Nugatory said:If you want to know how gravity behaves, classical Newtonian mechanics works well, and there are many excellent texts.
If you want to understand the current level of understanding of what gravity is and how it relates to mass and inertia, you'll have to spend some time learning what general relativity is about. There are s many bad pop-sci explanations out there that I'm reluctant to recommend a google search, but if you search through the relativity forum here you'll find some good answers (I particularly recommend member A.T.'s short video about an apple hanging on a branch and then falling) and also some good book recommendations.
James Gordon said:Care to comment?
Nugatory said:Only if you can provide a pointer to a peer-reviewed paper instead of "some people say". As I mentioned above, there's a lot of really bad pop-sci out there.
Nugatory said:Only if you can provide a pointer to a peer-reviewed paper instead of "some people say". As I mentioned above, there's a lot of really bad pop-sci out there.
Nugatory said:Only if you can provide a pointer to a peer-reviewed paper instead of "some people say". As I mentioned above, there's a lot of really bad pop-sci out there.
1. It is personal speculation with no motivation, and no evidence.James Gordon said:Well, it seems as though the jury is out for many people on what is actually causing inertia. I certainly don't know for a fact what that is. I simply would like to be pointed out what is absolutely not possible about my question on the topic. If a person cannot do so succinctly I have to suspect that they do not know the answer themself, by which I do not mean as an offense, but rather an inescapable impartiality.
jbriggs444 said:1. It is personal speculation with no motivation, and no evidence.
2. It makes no quantitative predictions.
3. Nugatory summed the situation up adequately in post #2.
jbriggs444 said:1. It is personal speculation with no motivation, and no evidence.
2. It makes no quantitative predictions.
3. Nugatory summed the situation up adequately in post #2.
logico said:J.G.
Your object persists in its state of rest or uniform motion in a straight line until acted upon by an external force - law of inertia. You are right, obviously, that the parts of the object are attracted to its centre of gravity, but that attraction cannot contribute to nor create inertia. Consider the moon, as Newton did. Every particle in the moon is attracted by the earth, but also tends to persist in "uniform motion in a straight line," the roughly circular orbit resulting. It is true that any particular lunar atom is attracted to the moon's centre, but that cannot affect the moon's inertia. Think of the lunar atom nearest to the Earth - does its acceleration towards the moon's centre cause resistance to the Earth's attraction? Well, obviously, since the moon doesn't (for a long while yet) rip apart. But there is a corresponding atom at the far point whose acceleration towards the centre adds to the acceleration towards the earth. Summed across the whole moon, there is no net resistance due to gravitational self attraction.
logico said:J.G.
Sorry - Principle of Equivalence.
Gravity is a fundamental force of nature that causes objects with mass to be attracted to one another. It is responsible for keeping planets in orbit around the sun and for keeping us grounded on Earth.
Gravity works by the principle of mass attraction. The larger an object's mass, the greater its gravitational pull. This pull decreases as the distance between two objects increases.
Gravity and inertia are both related to the movement of objects, but they are different concepts. Gravity is the force that pulls objects towards each other, while inertia is the tendency of an object to resist changes in its motion.
Gravity affects the human body in many ways. It keeps us on the ground, allows us to walk and run, and helps us maintain balance. In space, where there is less gravity, astronauts experience changes in their body, such as bone and muscle loss.
Yes, gravity and inertia can be manipulated through various means. For example, astronauts experience weightlessness in space because there is less gravity. Inertia can also be manipulated through external forces, such as a rocket's thrust, to change an object's direction or speed.