MigL Posted October 17, 2015 Share Posted October 17, 2015 Yes, let's explicitly specify the conditions. And then you tell us what is the difference, Michel123456. Two isolated systems, one of which has Studiot's cup on a ledge, and the other which has Swansont's ice cube on a ledge. Both the cup and the ice cube fall to the floor and shatter into pieces. Obviously neither will re-form in an isolated system, neither by natural, nor human intervention. Do a quick energy analysis, and tell us what is different Link to comment Share on other sites More sharing options...
studiot Posted October 17, 2015 Share Posted October 17, 2015 Hey, Mig be careful with my cup! Link to comment Share on other sites More sharing options...
michel123456 Posted October 18, 2015 Author Share Posted October 18, 2015 Yes, let's explicitly specify the conditions. And then you tell us what is the difference, Michel123456. Two isolated systems, one of which has Studiot's cup on a ledge, and the other which has Swansont's ice cube on a ledge. Both the cup and the ice cube fall to the floor and shatter into pieces. Obviously neither will re-form in an isolated system, neither by natural, nor human intervention. Do a quick energy analysis, and tell us what is different OK neither will reform "spontaneously". But if you do a quick energy analysis, none will fall "spontaneously" either. And you don't want to introduce human intervention in the scenario, because with human intervention you will see the cup reform and be put on the table again, against gravity. That was and still is my argument: if you want to explain and understand physics, don't take examples from the living world. And to me (let me be wrong on this), the living world extends also to the things created by life, like eggs, fruits, seeds, spermatozoids, nests, cups of tea, lamborghinis, skyscrapers, rockets, etc. Well, of course a rocket follows the laws of physics, but is a rocket explodes on the ground, do not expect to ever observe the reverse process, heat producing a rocket, for the same reason that heat cannot produce a cup, an egg or a plant "just like that" On the other side, heat can melt ice, heat can make water evaporate, and reducing heat can make water turn into ice again. One must explain why this cycle cannot be achieved ad infinitum in a closed system. And forget the cup analogy once for all. Link to comment Share on other sites More sharing options...
Sensei Posted October 18, 2015 Share Posted October 18, 2015 (edited) Of course heat alone will not make a cup. [...] When we change the cup with some other material that can indeed be rebuild without human help, then you say we were talking about a "isolated system" and you cannot input heat. It's not heat. It's conversion of internal energy (bonds between quarks, atoms, electrons and molecules), to kinetic energy of newly produced parts. Unbroken cup has one momentum for entire object. They act like one piece. After breaking each broken part has its own momentum, and flying in its own direction. Better illustration is quantum physics, fusion or decay of atom. f.e. Uranium-238 at rest will decay to Thorium-234 and Helium-4 with decay energy 4.267 MeV (in this case converted to kinetic energy of Th-234 and alpha particle, majority to alpha). Reverse of this process would be shooting alpha particles at Thorium-234 target to receive Uranium-238 back.. Chemistry equivalent experiment: we have KNO3, Sulfur and Carbon, all solid, after ignition they turn to gases, the better adjusted amounts, the more gas, and the more powerful explosion. Reverse of it would be turning these gases back to solid state KNO3, Sulfur, and Carbon from CO2, SO2, etc. But if you would catch all these gases, they would loose all their energies, in kinetic energy originally owned, and cool down, so they wouldn't be able to. Compounds are in lower energy state than they were initially, prior explosion. Edited October 18, 2015 by Sensei Link to comment Share on other sites More sharing options...
michel123456 Posted October 18, 2015 Author Share Posted October 18, 2015 (edited) It's not heat. It's conversion of internal energy (bonds between quarks, atoms, electrons and molecules), to kinetic energy of newly produced parts. That's all details to me but it looks to me that a cup falling has kinetic energy (from human hand or simply falling by gravity) and the kinetic energy is spread to all the pieces. Your description looks like an explosion, not like a desctruction caused by the impact. Unbroken cup has one momentum for entire object. They act like one piece. After breaking each broken part has its own momentum, and flying in its own direction. So what? Is that entropy? Better illustration is quantum physics, fusion or decay of atom. f.e. Uranium-238 at rest will decay to Thorium-234 and Helium-4 with decay energy 4.267 MeV (in this case converted to kinetic energy of Th-234 and alpha particle, majority to alpha). Reverse of this process would be shooting alpha particles at Thorium-234 target to receive Uranium-238 back.. Chemistry equivalent experiment: we have KNO3, Sulfur and Carbon, all solid, after ignition they turn to gases, the better adjusted amounts, the more gas, and the more powerful explosion. Reverse of it would be turning these gases back to solid state KNO3, Sulfur, and Carbon from CO2, SO2, etc. But if you would catch all these gases, they would loose all their energies, in kinetic energy originally owned, and cool down, so they wouldn't be able to. Compounds are in lower energy state than they were initially, prior explosion. I bet you have also eluded human intervention in this example. It is not an analogy from which one can take a conclusion. Edited October 18, 2015 by michel123456 Link to comment Share on other sites More sharing options...
Sensei Posted October 18, 2015 Share Posted October 18, 2015 (edited) Explosion turns solids to gases, or liquids to gases. While breaking solid in parts, like breaking cup, newly made parts generally remain in the same state of matter. However some atoms can change state on the edge. f.e. meteors are melting in air while passing by atmosphere. They change state because of enormous energy. Edited October 18, 2015 by Sensei Link to comment Share on other sites More sharing options...
swansont Posted October 18, 2015 Share Posted October 18, 2015 OK neither will reform "spontaneously". But if you do a quick energy analysis, none will fall "spontaneously" either. No? Thing never fall over without a push? And you don't want to introduce human intervention in the scenario, because with human intervention you will see the cup reform and be put on the table again, against gravity. That was and still is my argument: if you want to explain and understand physics, don't take examples from the living world. And to me (let me be wrong on this), the living world extends also to the things created by life, like eggs, fruits, seeds, spermatozoids, nests, cups of tea, lamborghinis, skyscrapers, rockets, etc. Well, of course a rocket follows the laws of physics, but is a rocket explodes on the ground, do not expect to ever observe the reverse process, heat producing a rocket, for the same reason that heat cannot produce a cup, an egg or a plant "just like that" On the other side, heat can melt ice, heat can make water evaporate, and reducing heat can make water turn into ice again. One must explain why this cycle cannot be achieved ad infinitum in a closed system. And forget the cup analogy once for all. We can discuss entropy of things not made by humans, or the living world. The results are exactly the same, so your contention that living things somehow make for a different problem leaves no trace in the analysis. Your objection doesn't become true by repetition. Link to comment Share on other sites More sharing options...
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