Perpetua mobile theoretical misunderstanding

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The discussion centers on the theoretical misunderstanding of perpetual motion machines, specifically regarding a scenario where a metal ball is accelerated by a tubular permanent magnet. The user acknowledges the conservative nature of magnetic fields but struggles to comprehend why the ball would not maintain acceleration after leaving the tube. They question the relationship between force, magnetic fields, and the ball's velocity, particularly when the ball is stationary. The conversation highlights the complexities of magnetic forces and the impossibility of perpetual motion, with a reminder that such machines are not discussed on the forum. Understanding the limitations of magnetic fields is crucial in addressing these misconceptions.
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Hello

I was patent examiner on the Portuguese patent office for 3 years and we have a lot of perpetua mobile applications, so I wanted to find now, the theoretical misunderstanding I'm missing here

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Imagine you have a track (on a table, on the xOy plane) on which a metal ball would follow, and at a certain length of the track, there would be a tubular permanent magnet, that would create a force on the ball accelerating it. That ball would be accelerated every time it passes through the tube!

I know that there is some paradox on my lemma, but I can't find where

Thank you in advance

PS: Actually I know that the magnetic field is conservative, but something is missing
 

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The tube will not accelerate the ball around the track. I'm not sure what will happen inside the tube since the flux is so uniform, but once the ball leaves the tube it will be attracted right back to it.
 
That's what I can't understand because every time I see images of magnetic field I see this

310px-Earths_Magnetic_Field_Confusion.svg.png


By the way, I know that the force is F=q(E + v\times B)

But how to relate the Force created by the magnetic field of a permenant magnet if the ball is stopped, v=0, and there is no Electric field

You said the ball would came back, but can't we shield the field, so the field just applies inside the tube.

Sorry, too many questions
 
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Sorry, but we do not discuss perpetual motion machines on PF.
 
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