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Author Topic: Light speed magnetism  (Read 602 times)

Offline ProjectSailor

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Light speed magnetism
« on: 14/09/2015 12:15:03 »
Okay, magnets in hand.. we are travelling just short of the speed of light 0.99c dont know how we got that fast.. but that doesnt matter..

We fly past a clump of say iron filings.. the magnet attracts the iron filings.. instantly speeding them up to our speed (well almost of course.. I dare say it would have an impact but bear with)

Firstly, forgive my ignorance, but where does the energy come from when a fixed magnet attracts material.. I am going to stick with magic.. but I would benefit from education!

More importantly.. IF those iron filings were actually travelling past me at the speed of light and were heavier than I.. do we get attracted to them and actually speed up?

This then leads me to.. IF I were travelling at 0.9c in starship enterprise.. and shot a magnet ever so slightly in front of me out the torpedo tube, would that magnet attract me (newton says yes) and if i continuted to do so, speeding up ever so slightly each time up to c, would I then be able to do it again? (why couldn't I?) would this then speed me up past the speed of light?

Theres probably a physics safety catch in there somewhere that stops me firing my magnet torpedo at the speed of light obviously something to do with the speed of the magnetic waves or something..

Okay lets ratchet it down a notch..

Body A
Magnet B
A+B travelling at 50m/s
Eject B (self propelled ofc none of this reaction force on A malarky thank you very much) at 51m/s
A attracts B and B attracts A  we end up with A+B travelling at 50.5m/s (if body's are identical masses i assume?)

and since this is magic driving this, could this be a way of propelling space craft?


 

Offline PmbPhy

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Re: Light speed magnetism
« Reply #1 on: 15/09/2015 02:32:34 »
Quote from: ProjectSailor
Okay, magnets in hand.. we are travelling just short of the speed of light 0.99c dont know how we got that fast.. but that doesnt matter..

We fly past a clump of say iron filings.. the magnet attracts the iron filings.. instantly speeding them up to our speed (well almost of course.. I dare say it would have an impact but bear with)

Firstly, forgive my ignorance, but where does the energy come from when a fixed magnet attracts material.. I am going to stick with magic.. but I would benefit from education!
This is a complex issue. It's something that's rarely discussed in the literature. It's the fact that a magnetic field cannot to work. So the work is done by the electric fields created by the charges inside the magnet.


Quote from: ProjectSailor
More importantly.. IF those iron filings were actually travelling past me at the speed of light and were heavier than I.. do we get attracted to them and actually speed up?
Since nothing can move at the speed of light there can be no answer to your question. I need to brush up on this so this post is just a temporary step. I'll make the following journal articles available to you if you wish to read them. They are

Work done on charged particles in magnetic fields by Charles A. Coombes, Am. J. Phys., 47(10), Oct. (1979)

Magnetic Forces Doing Work by Eugene P. Mosca, Am. J. Phys., 42(4), Apr. (1974)

Essentially there are electric fields which do the work. Those fields come from the charges which make up the currents which make up a magnet.
 

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Re: Light speed magnetism
« Reply #1 on: 15/09/2015 02:32:34 »

 

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