Timeline for Don't heavier objects actually fall faster because they exert their own gravity?
Current License: CC BY-SA 3.0
10 events
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| Mar 11, 2024 at 22:53 | comment | added | ErikE | Yeah, I was being a bit mulish the first time I encountered this explanation. I wasn't properly allowing for how "the earth and all the things in it" is a closed system. The acceleration of two objects toward each other varies with the sum of their masses. We can't just materialize a hammer that didn't exist before. So the total system's mass doesn't change. This is actually a fascinating problem! | |
| May 22, 2015 at 23:18 | comment | added | ErikE | I take it back, at least a little, due to reading another answer of yours that I either read more carefully or that explained better. I'm open to the possibility that serially picking up a light object and a heavy object would encounter the effect you're mentioning (where the heavy object would not fall faster because the "Earth" has had its mass reduced by more in that case), but I'm not sure at this point. | |
| Aug 5, 2014 at 19:57 | review | Suggested edits | |||
| Aug 5, 2014 at 20:26 | |||||
| Dec 20, 2012 at 20:57 | history | edited | Nick | CC BY-SA 3.0 | Added a citation. I specialize in the radial two body problem, and I have had these discussions before. |
| Dec 8, 2012 at 21:09 | comment | added | ErikE | It makes no difference. It's a human reference frame to imagine the Earth to be still. But that is illogical. The Earth is not fixed in space. It moves due to acceleration imparted on it by other objects! Stop thinking about when the second object is introduced. Calculate everything after that. The scenario is: two objects in an otherwise empty universe, one very massive, one of unknown mass, are in airless free fall, held apart by a force. When the force separating them is removed, they both accelerate towards each other. The mass of #2 affects the time until impact. | |
| Dec 8, 2012 at 20:56 | history | edited | Nick | CC BY-SA 3.0 | Added some math as requested. |
| Dec 8, 2012 at 20:45 | comment | added | Nick | @ErikE There are two scenarios. In the first, the total mass of the system is constant (you split the Earth into two pieces). In the second, the total mass of the system increases (you introduce new mass). | |
| Dec 8, 2012 at 15:27 | history | edited | Nick | CC BY-SA 3.0 | Typos |
| S Dec 8, 2012 at 15:03 | history | answered | Nick | CC BY-SA 3.0 | |
| S Dec 8, 2012 at 15:03 | history | made wiki | Post Made Community Wiki by Nick |