Lan Todak Posted December 30, 2019 Share Posted December 30, 2019 Why we calculate total mass of a subject? Link to comment Share on other sites More sharing options...
Strange Posted December 30, 2019 Share Posted December 30, 2019 9 minutes ago, Lan Todak said: Why we calculate total mass of a subject? Why? So that we know the total mass. Quote Something's wrong with the way we calculate mass ! Moderator Note Do I need to move this to Speculations? Do you have an alternative theory you are proposing? Link to comment Share on other sites More sharing options...
Mordred Posted December 30, 2019 Share Posted December 30, 2019 12 minutes ago, Lan Todak said: Why we calculate total mass of a subject? So we know the total resistance to inertia change. Link to comment Share on other sites More sharing options...
Janus Posted December 30, 2019 Share Posted December 30, 2019 Strange has already answered your question. Why do you think there is something wrong with the way we calculate mass? Link to comment Share on other sites More sharing options...
Sensei Posted December 30, 2019 Share Posted December 30, 2019 (edited) Mass of what? Mass of small things is measured on weigh. Mass of uniform things is calculated from average density muliplied by volume of an object. e.g. mass of the all oceans can be calculated from volume, obtained from depth maps, muliplied by density 1 kg/L. Mass of astronomical objects like planets is calculated from gravitational acceleration of an object. Mass of macroscopic objects is sum of masses of constituents. Measure mass of single average grain of sand, calculate volume of a beach, and you will know average quantity of grains. The same is with atoms. Therefore we can convert mass to moles in chemistry. Edited December 30, 2019 by Sensei Link to comment Share on other sites More sharing options...
Lan Todak Posted December 30, 2019 Author Share Posted December 30, 2019 (edited) Let say if i had a golden rod,1000000 km in width and 1 km in diameter. Could you calculate gravity at the center of that rod? 27 minutes ago, Strange said: Why? So that we know the total mass. ! Moderator Note Do I need to move this to Speculations? Do you have an alternative theory you are proposing? maybe later... since i did not purpose any theory yet. length* Edited December 30, 2019 by Lan Todak Link to comment Share on other sites More sharing options...
swansont Posted December 30, 2019 Share Posted December 30, 2019 17 minutes ago, Lan Todak said: Let say if i had a golden rod,1000000 km in width and 1 km in diameter. Could you calculate gravity at the center of that rod? Yes. Apply Newton's law to it. Symmetry indicates that it's zero. (any dV I pick has a partner equidistant from the center and in the exact opposite direction) What's your point? Link to comment Share on other sites More sharing options...
Lan Todak Posted December 30, 2019 Author Share Posted December 30, 2019 36 minutes ago, swansont said: Yes. Apply Newton's law to it. Symmetry indicates that it's zero. (any dV I pick has a partner equidistant from the center and in the exact opposite direction) What's your point? How about at the ends of the rod?would you get some values? what happened if you split the rod into 2 identical rods. so that the center became 2 new ends. would that give you values instead of zero referring of your result? just answer my questions first then i will let you know... Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted December 30, 2019 Share Posted December 30, 2019 1 hour ago, Sensei said: Mass of what? Mass of small things is measured on weigh. Mass of uniform things is calculated from average density muliplied by volume of an object. e.g. mass of the all oceans can be calculated from volume, obtained from depth maps, muliplied by density 1 kg/L. Mass of astronomical objects like planets is calculated from gravitational acceleration of an object. Mass of macroscopic objects is sum of masses of constituents. Measure mass of single average grain of sand, calculate volume of a beach, and you will know average quantity of grains. The same is with atoms. Therefore we can convert mass to moles in chemistry. This being a relativity thread, it could, and generally would, be greater than that. Link to comment Share on other sites More sharing options...
Lan Todak Posted December 30, 2019 Author Share Posted December 30, 2019 1 hour ago, swansont said: Yes. Apply Newton's law to it. Symmetry indicates that it's zero. (any dV I pick has a partner equidistant from the center and in the exact opposite direction) What's your point? You need to plot the value into a graph. from the center to the ends of the rod. you will get zero to asymptotically zero. Link to comment Share on other sites More sharing options...
swansont Posted December 30, 2019 Share Posted December 30, 2019 1 hour ago, Lan Todak said: How about at the ends of the rod?would you get some values? what happened if you split the rod into 2 identical rods. so that the center became 2 new ends. would that give you values instead of zero referring of your result? just answer my questions first then i will let you know... At the end of the rod you will get the integrated value of M/r^2 Any scenario with the symmetry I described will give you zero. 19 minutes ago, Lan Todak said: You need to plot the value into a graph. from the center to the ends of the rod. you will get zero to asymptotically zero. No, you will get zero at the center, and a nonzero value away from center. I expect it will be a maximum at the end of the rod, since that situation would have the most, and closest, mass contributing to the net result. Link to comment Share on other sites More sharing options...
md65536 Posted December 30, 2019 Share Posted December 30, 2019 3 hours ago, J.C.MacSwell said: 4 hours ago, Sensei said: Mass of macroscopic objects is sum of masses of constituents. This being a relativity thread, it could, and generally would, be greater than that. How do you figure it would be greater? You must have conservation of mass+energy. Since we're talking about only mass, the energy of an object or a system of "constituents" wouldn't matter (and is unspecified anyway). I thought maybe you meant there is some new particle that only exists when other particles are combined, like maybe gluons, but those are likely massless. For your statement to be true, I figure either you'd have to have different constituents when an object is considered as a whole vs as parts, or you'd have to change the mass of individual constituents??? What makes up the difference in mass? Link to comment Share on other sites More sharing options...
MigL Posted December 31, 2019 Share Posted December 31, 2019 10 minutes ago, md65536 said: You must have conservation of mass+energy Exactly ! You cannot combine the three quark constituents of a proton without their binding. The individual masses of the three quarks would be equivalent to a couple of percent of the mass of the proton. It is the binding energy equivalence that makes up the vast majority of the proton's mass. That is what JC was alluding to. 2 Link to comment Share on other sites More sharing options...
Lan Todak Posted December 31, 2019 Author Share Posted December 31, 2019 17 hours ago, swansont said: At the end of the rod you will get the integrated value of M/r^2 Any scenario with the symmetry I described will give you zero. No, you will get zero at the center, and a nonzero value away from center. I expect it will be a maximum at the end of the rod, since that situation would have the most, and closest, mass contributing to the net result. How atoms knew that they were farther away from the center? Does atom have such indicator to indicate coordinates? 21 hours ago, Sensei said: Mass of what? Mass of small things is measured on weigh. Mass of uniform things is calculated from average density muliplied by volume of an object. e.g. mass of the all oceans can be calculated from volume, obtained from depth maps, muliplied by density 1 kg/L. Mass of astronomical objects like planets is calculated from gravitational acceleration of an object. Mass of macroscopic objects is sum of masses of constituents. Measure mass of single average grain of sand, calculate volume of a beach, and you will know average quantity of grains. The same is with atoms. Therefore we can convert mass to moles in chemistry. How about temperature and luminosity? Link to comment Share on other sites More sharing options...
Mordred Posted December 31, 2019 Share Posted December 31, 2019 Atoms don't think or read indicators. They simply respond to their respective fields through attraction and repulsion interactions. 1 Link to comment Share on other sites More sharing options...
MigL Posted December 31, 2019 Share Posted December 31, 2019 3 hours ago, Lan Todak said: How atoms knew that they were farther away from the center? Does atom have such indicator to indicate coordinates? Or, to put it according to GR ( if you don't like 'spooky' action at a distance ), they simply follow the local space-time curvature ( geodesic ). Link to comment Share on other sites More sharing options...
Lan Todak Posted December 31, 2019 Author Share Posted December 31, 2019 3 hours ago, Mordred said: Atoms don't think or read indicators. They simply respond to their respective fields through attraction and repulsion interactions. if we ask a person to sit in a box and tie the box with different length ropes . when we pull any of the ropes with equal strength and direction, does he know which one? if atom is exerted with forces from various distances, that atom will interact according to directions and strengths of those forces only. atom is not experiencing any distances. Link to comment Share on other sites More sharing options...
MigL Posted December 31, 2019 Share Posted December 31, 2019 The words 'equal strength' are not well defined physics terms. If instead you use 'force', which is well defined, and gives rise to an acceleration, then, yes, you absolutely know which rope/direction. Just as when you're in an elevator, even with your eyes closed so you don't see the floor number, you can tell if you're going up or down. 12 minutes ago, Lan Todak said: atom is not experiencing any distances. That is one of the problems with Newtonian gravity ( action at a distance ) that A Einstein set out to remedy with GR, which is simply mass following space-time curvature. Link to comment Share on other sites More sharing options...
swansont Posted December 31, 2019 Share Posted December 31, 2019 1 hour ago, Lan Todak said: if we ask a person to sit in a box and tie the box with different length ropes . when we pull any of the ropes with equal strength and direction, does he know which one? What does this have to do with gravity, which does not have equal strength? 1 hour ago, Lan Todak said: if atom is exerted with forces from various distances, that atom will interact according to directions and strengths of those forces only. atom is not experiencing any distances. It experiences an interaction, whose strength is dependent on distance Link to comment Share on other sites More sharing options...
Strange Posted December 31, 2019 Share Posted December 31, 2019 1 hour ago, Lan Todak said: if we ask a person to sit in a box and tie the box with different length ropes . when we pull any of the ropes with equal strength and direction, does he know which one? if atom is exerted with forces from various distances, that atom will interact according to directions and strengths of those forces only. atom is not experiencing any distances. ! Moderator Note You have been told that it is the field which changes with distance so atoms do not need to "know" the distance. If you do not start engaging seriously, this thread will be closed. Link to comment Share on other sites More sharing options...
Mordred Posted December 31, 2019 Share Posted December 31, 2019 (edited) 3 hours ago, Lan Todak said: if we ask a person to sit in a box and tie the box with different length ropes . when we pull any of the ropes with equal strength and direction, does he know which one? if atom is exerted with forces from various distances, that atom will interact according to directions and strengths of those forces only. atom is not experiencing any distances. I'm curious as to why you keep trying to visualize an atom with some form of sentient life. ? No particle thinks... it cannot know anything The mass term of every particle is due to its coupling strength to their respective fields that the particle interacts with. Mass is defined as resistance to inertia change. There are no ropes involved so the above makes no sense. As others have already mentioned there are forces involved and each force has a ratio of change due to distance. Edited December 31, 2019 by Mordred Link to comment Share on other sites More sharing options...
Lan Todak Posted January 1, 2020 Author Share Posted January 1, 2020 Since i have been given warning so i will go straight to the point. our solar system is well fine tuned so everything seems stable from going to disorder. because of that, energy looks conserved in every confined body. but globally that's not the case. total mass should be calculated of certain area or volume rather than of body when involving chaotic systems. https://en.wikipedia.org/wiki/Three-body_problem //I will go on vacation and will be back.. 😃. Link to comment Share on other sites More sharing options...
Strange Posted January 1, 2020 Share Posted January 1, 2020 1 hour ago, Lan Todak said: Since i have been given warning so i will go straight to the point. our solar system is well fine tuned so everything seems stable from going to disorder. because of that, energy looks conserved in every confined body. but globally that's not the case. total mass should be calculated of certain area or volume rather than of body when involving chaotic systems. https://en.wikipedia.org/wiki/Three-body_problem //I will go on vacation and will be back.. 😃. ! Moderator Note When you come back, you can start a new thread in Speculations. That thread must provide the mathematics behind this idea. And show how that matches what we observe. Link to comment Share on other sites More sharing options...
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