Where does the energy come from?

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Discussion Overview

The discussion revolves around the source of energy in a system involving a permanent magnet and a laminated yoke, where magnetic flux changes are used to generate electricity. Participants explore concepts related to magnetic fields, energy transfer, and the mechanics of the system, touching on both theoretical and practical aspects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions the source of energy for electricity generation in a system involving a moving telescopic piece within a magnetic field, suggesting that it might come from the physical force applied to move the piece.
  • Another participant references a "perpetual motion" video, dismissing it as a hoax and implying skepticism about the feasibility of such machines.
  • A different participant suggests that the energy comes from the work done to move the telescopic piece, referencing an ancient machine called the electrophorus that generates static electricity through movement.
  • One participant speculates that energy might be derived from heat energy absorbed in the apparatus, discussing the potential effects of eddy currents and magnetic shielding on the system's energy dynamics.
  • A later reply proposes that the arm behaves like a solenoid, indicating that an overcoming force is necessary to open it, which is where the energy is sourced from.

Areas of Agreement / Disagreement

Participants express varying viewpoints on the source of energy in the system, with no consensus reached. Some propose that energy comes from mechanical work, while others speculate about the role of heat and magnetic effects, indicating ongoing debate and uncertainty.

Contextual Notes

Participants mention concepts such as eddy currents and magnetic shielding without fully resolving their implications or the conditions under which they apply. The discussion reflects a range of assumptions and lacks definitive conclusions about the energy dynamics involved.

philrainey
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if you have a permanent magnet slotted into a laminated yoke like a transformer has. But this yoke has a telescopic piece which is made in the from of a bunch of wires running in line with the magnetic field . if this piece is pulled shut and open to increase and decrease the magnetic path resistance and there is a coil on the yoke and the increasing and decreasing magnetic flux creates electricity where does the energy for the electricity come from. I guess it comes from the phsyical force of moving the telespcopic piece but since this hopefully has little current in it is laminated to reduce eddy currents where does it get its' magnetic field from to resist movement. Can someone please explain this so I can stop thinking about it and get on with fixing my house.
 
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Have you seen the "perpetual motion" video of a similar machine? If so, that's a hoax. Enjoy fixing your house.
 
er, the energy comes from work you spend to do so.

There was an ancient, sorry prehistoric machine called ELEKTROPHORUS, sorry if i misspelt, that used to generate static electricity by moving a gatapercha or ebonite disk away and against attraction of a charged one.

BUT THERE might well be flaws in this explanation -- i will probe.
 
To tell the truth I did have in the back of my mind a fantasical machine of a perpetual motion kind. I have learned about magnetic refrigeration so I was dimly hoping that the energy may come from heat energy been absorped somewhere in the apparatus. the energy to move the telescopic ( I'm going to call it a arm but it does not swing )you have the F=ma to accelerate it and a little resistance ? caused by eddy currents in the insulated sections which creates a magnetic field of their own to resist the movement. But perhaps these currents can be nearly eliminated or perhaps a magnetic sheilding material could be inserted and uninserted into the yoke, I don't know anything about magnetic sheilds but perhaps they don't conduct electricity very good so would not conduct eddy currents.
 
Last edited:
I think I get it now the arm is always trying to shut because it acts like a solenoid so there is a overcoming force that must be applied to open it which is where all the energy comes from.
 

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