Author Topic: Troll Science - Propulsion with Magnets?  (Read 2160 times)

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Offline Ultra

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Troll Science - Propulsion with Magnets?
« on: September 28, 2011, 10:19:49 PM »

Will it work?

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Offline Azdgari

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Re: Troll Science - Propulsion with Magnets?
« Reply #1 on: September 28, 2011, 11:08:16 PM »
For some reason I had to paste the link into my browser to see it.

Anyway, no it won't, because the approaching magnets on the wheel will be first repelled as they approach the outer magnets (slowing the wheel down), and then be repelled again (to speed it up).  The torque given by each of these will be the same.

That said, my objection only applies to the way it's laid out so far.  A more complex machine, one which retracted the magnets and then put them back out in time to spin the wheel around, would work.  But then you'd need an energy source that could push the wheel's magnets back out against the repulsive force of the outer magnets (or vice versa), and that would defeat the whole purpose of the machine.
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Offline Ultra

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Re: Troll Science - Propulsion with Magnets?
« Reply #2 on: September 29, 2011, 08:05:41 AM »
http://s2.postimage.org/webvcdyys/Troll_Science.jpg
Heres the link for the image, if it doesn't show up.

So the spinning of the wheel could not be extended unless the the fields of Magnet A and B are reversed to pull and only then push the smaller magnets?

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Offline Azdgari

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Re: Troll Science - Propulsion with Magnets?
« Reply #3 on: September 29, 2011, 08:40:41 AM »
Yes, if they're electromagnets and you can reverse the charge, then that works.  Which would actually be similar to how a standard electric motor works, in principle.

Of course, electromagnets need to be powered...
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Offline Historicity

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Re: Troll Science - Propulsion with Magnets?
« Reply #4 on: September 29, 2011, 09:27:13 AM »
I can't see any reasoning at all behind this.

For instance, there are + on the diagram for instance.  There is no positive charge in magnetism nor a negative.   The charges on magnets are called North and South.  This isn't just a nicety of customary situational terminology[1] , N and S and + and - are really different things.

As far as I can see the magnets repel the magnets coming towards them and repel them when they are going away.  That would be balanced and there isn't even a plausibility of a net gain.

Now for more detail.  I have studied electromagnetism.

There would also be a net loss.  When a magnet moves past some medium that can be magnetized (iron and other ferromagnetic metals such as cobalt are obvious) it induces an electric current in them that moves in a circle. This is called an eddy current. The electric current is always in such a direction that it creates an opposing magnetic field.  So as a magnet moves towards a metal it creates its own repulsion force (however slight) and as it moves away it creates a slight extra attraction force.  Likewise an eddy current is set up inside the magnet.  The eddy currents are in a medium that has electrical resistance.  This becomes a heat loss.  So some of the motion energy of the magnet is lost and as usually happens it ends up as waste heat.  This is called hysteresis loss. 

BTW, look at a transformer or the armature of an electric motor.  Have you ever wondered why they are not solid but made up of a bunch of metal plates?  The reason is those plates are glued together and are electrically insulated from each other.  The eddy currents are kept tiny and there is less loss. Another method is a magnetic core which is iron powder glued together.  In the early days of electricity, the late 1880s, a company Eickemeyer[2] built huge dynamoes that produced mediocre power especially compared to the input power.  Charles Steinmetz solved (as best as it could be solved) the hysteresis effect.

 1. You can brag about the gigabytes and the clock speed of your computer but what about its horsepower?  I have a 1/5 hp computer.  That is 1 hp = 746 watts.  The use of horsepower for cars and watts for electrical devices is a customary matter.
 2. Bought out by General Electric in 1893

Offline Omega

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Re: Troll Science - Propulsion with Magnets?
« Reply #5 on: September 29, 2011, 12:10:50 PM »
common misunderstanding here is that magnetic lines are not like jet streams, they are like nonlinear rubber bands that do not ever break
so it is foolish to use magnets as turbine nozzles

to make it work you need periodically break these rubber bands  with external force and create new ones
that is how electric motor work.