The 1st law of thermodynamics “that energy can not be created or destroyed, it can only be changed from one form to another” is the question here.. If I have matter, and was able to convert this matter into energy @ E=mc2, what happens to potential energy 'held' by the matter?
springs.pdf attached shows the idea.. I have a container with a spring in it, in one case the spring is held in a stretched state (energy has been used to stretch the spring, some energy has been converter to heat in the process of stretching the spring, but now the spring is trapped in a stretched state, and has potential energy which can do work and therebye be converted to energy in some other form [recovered]).. I also have shown this spring in an unstretched state in the same containment.. This spring has no (elastic) potential energy.
If I convert both the containment and the spring to energy using E=mc2,
I cannot see how more energy would be produced from the stretched version than from the unstretched version (I have included the container so that no errors could result from energy imparted by sudden [!] removal of the spring).
If energy recovered is the same in both cases, then what has happened to the potential energy 'held' by the stretched spring..?
If energy is not the same in both cases, please explain how this can be.. I have been tortured by this problem (and many other variants involving other potential energy types) for days.. If I am being stupid, Please show me (simply) why, as I am obviously as thick as 2 short planks!
As I see it, the only way to get a different energy from E=mc2 would be to change m, as c is a constant.. therefore, in order to recover the potential energy held by a stretched spring, m for the spring+enclosure must be greater when the spring is stretched than when the spring is at rest.. this does not seem right to me!
springs.pdf attached shows the idea.. I have a container with a spring in it, in one case the spring is held in a stretched state (energy has been used to stretch the spring, some energy has been converter to heat in the process of stretching the spring, but now the spring is trapped in a stretched state, and has potential energy which can do work and therebye be converted to energy in some other form [recovered]).. I also have shown this spring in an unstretched state in the same containment.. This spring has no (elastic) potential energy.
If I convert both the containment and the spring to energy using E=mc2,
I cannot see how more energy would be produced from the stretched version than from the unstretched version (I have included the container so that no errors could result from energy imparted by sudden [!] removal of the spring).
If energy recovered is the same in both cases, then what has happened to the potential energy 'held' by the stretched spring..?
If energy is not the same in both cases, please explain how this can be.. I have been tortured by this problem (and many other variants involving other potential energy types) for days.. If I am being stupid, Please show me (simply) why, as I am obviously as thick as 2 short planks!
As I see it, the only way to get a different energy from E=mc2 would be to change m, as c is a constant.. therefore, in order to recover the potential energy held by a stretched spring, m for the spring+enclosure must be greater when the spring is stretched than when the spring is at rest.. this does not seem right to me!
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