B A Magnetic Misconception on Divergence 0/Closed Field Lines?

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The discussion centers on whether closed magnetic field lines imply that magnetic forces do no net work, questioning the misconception surrounding this concept. It draws a parallel to electric fields, noting that closed field lines between opposite electric charges do not prevent work from being done on those charges. The conversation highlights that while magnetic forces may not do work on charges in a closed loop, electric fields can still perform work despite having closed lines, as seen in the case of an electric dipole. The key takeaway is that the presence of closed field lines does not inherently mean that no work can be done by the associated forces. Understanding the distinction between magnetic and electric fields is crucial in this context.
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Question: Can we ultimately atttribute no work or net zero work done by a magnetic force to the closed magnetic field lines that results in Divergence zero of a magnetic field? That is, is it a misconception to say that closed magnetic field lines imply magnetic force will always result in no net work?

(I meant misconception on my part not theory.)

Edit: Why misconception? Now switch to electric field. The field lines between two opposite electric test charges are also closed and resemble that of a bar magnet, though electric in nature. Does it hold? Is it enough to say that since the field lines are closed between the two test charges that no net work can ever be done?
 
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Work done by a magnetic force on what ? Electric charge ?
 
Electric charge is all I can see (thinking back to Griffith's book).
 
Consider the electric field of an idealized electric dipole. It has only closed field lines, but it can do work on a charge.
 
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Thread 'Why higher speeds need more power if backward force is the same?'

Thread 'Why higher speeds need more power if backward force is the same?'

Power = Force v Speed Power of my horse = 104kgx9.81m/s^2 x 0.732m/s = 1HP =746W Force/tension in rope stay the same if horse run at 0.73m/s or at 15m/s, so why then horse need to be more powerfull to pull at higher speed even if backward force at him(rope tension) stay the same? I understand that if I increase weight, it is hrader for horse to pull at higher speed because now is backward force increased, but don't understand why is harder to pull at higher speed if weight(backward force)...
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