Magnet Driven   (Read 2071 times)

Well, as random thoughts tend to do, I had an idea this morning just as I was about to head to bed.

I was thinking about magnets -- of course I was thinking about magnets, what else would I possibly be thinking about? :p And visualising the way magnets attract and repel each other based on their pole alignment. That is, the north pole will attract the south pole of another magnet and two of the same poles will repel.

When I was a kid I used to muck about with the fairly powerful magnets that you find inside of speakers -- of course this was what I did as a kid, what else would I possibly do? :p I would play around with paperclips on strings and have the magnet make the paperclip hover in mid-air by fixing the string just far enough away that the magnet's attraction took hold but the string prevented the paperclip from ever touching the magnet.

** Rakuli! Quit your waffling and nostalgic nonsense and get to the point.. **

Alright, alright!

So I was thinking of the way magnets work by attracting and repelling and then started thinking about our desire to find a replacement for petroleum. There is a search for something clean that can power our vehicles. Hydrogen cells and ethenol are options that are being explored but...

What if we removed the need for fuel at all and instead employed the power found in magnets?


Here is what I envision as a way we could propel our "cars" using magnets...


Overlay the existing road infrastructure with magnetic material with the north pole facing the sky. This would provide the foundation.

Our actual cars could then be comprised of a strong magnet forming the floor of the car. The north pole of this floor magnet faces the ground (the north pole of the surface magnet). This creates the magnetic repulsion that suspends the car above the surface. The car is a weighted to a point where it remains a designated distance from the surface (say 30cm).

We now have a car that is suspended above the road so much of the friction found in land travel is removed leaving us to devise a way to propel the vehicle.

Propulsion could come from an electro-magnet in the front of the car, this can be powered up and down to control speed. The car is also heavily weighted at the back to avoid it tipping forwards onto its nose when the front magnet is active.

Now, the magnet at the front of the car has its south pole at a 45 degree angle facing down towards the road. When the magnet is active, it is attracted to the north pole of the road. Due to the weight at the back of the car preventing the front magnet from meeting the road, it is propelled along the road due to the angle it is facing. So...

Using no power except that required to power the front magnet, we create "flight" using magnet repulsion and attraction.


I have rushed to write this as I didn't want it to disappear but I am unsure how credible or possible this is. I will have a look into it and come up with some diagrams to illustrate my meaning better. I would appreciate any informed feedback or elaborations you might have on this.

Thanks for listening.

I must say that is an interesting theory but the down sides I see to this is that people would then have to be careful of wearing anything metal otherwise they would be stuck to the road, haha. Also the amount of people/ objects in the car would change things such as closer or higher to the ground or if enough weight put at one end then flip the car right over

Hi Rakuli! I liked this idea so much that I thought it worthy of a proper response. So I had to join your forums.

Magnetic levitation already exists, and can be used to create efficient transport, such as Maglev trains. The reduction in friction gives such vehicles the potential to reach very high speeds.

The problem with your idea is energy conservation. It's seductive to see the levitating paperclip, and think that this force can be harnessed for free energy. But one of the most fundamental laws of physics states that energy is conserved. Energy can be neither created nor destroyed, only changed from one form into another. The total amount of energy in the universe is a constant (and most of it is tied up in the form of mass).

What you're describing is a perpetual motion machine: a device that creates endless motion, without requiring any energy input (or force, if you prefer). Early scientists (back when they were all philosophers) were fascinated by the idea of perpetual motion. But nowadays, we believe that perpetual motion is impossible, because it would violate the law of conservation of energy.

There are many practical problems with your idea, such as how you'd prevent the cars from flipping over. But let's open our minds for a moment: suppose you could overcome these problems, and suppose it was economically viable. What would happen?

Well, the strength of your magnets would weaken over time: potential energy of the magnets would be changed into kinetic energy of the vehicle. The more you used the roads, the weaker their magnetism would become.

You could use electromagnets, of course, but then you need a power supply (note the interesting relationship between magnetism, movement, and electricity: moving a magnet can create electricity, or electricity can move the magnet). This is what the Maglev trains do, but that electricity is not free.

So, although magnetic levitation can reduce friction, it's not a source of free energy. Magnets are neat, but they're not magical.

Check out the Wikipedia entry on perpetual motion techniques (involving magnets): http://en.wikipedia.org/wiki/Perpetual_motion#Techniques


Magnetic levitation: http://en.wikipedia.org/wiki/Magnetic_levitation
Maglev trains: http://en.wikipedia.org/wiki/Maglev_train#Maglev_vs._conventional_trains

Hey Mike! It's good to see you here, it is minds like yours that I dearly wanted to start congregating on this site when I was creating it.. Unfortunately I have haven't put anywhere near as much time as I would have liked into this site recently :$

Thank you very much for giving some perspective on the topic, it is very interesting. I had heard about the Maglev trains before tring to use the idea in a more personal form of transport but never really looked much into the technology behind them.

A trait of new ideas that cross my mind is that they don't hang around too long trying to disprove themselves, especially at 5:30am (and that wasn't from me getting up early).

In the few weeks after writing this post I did some research and fact finding in an attempt to overcome some of the prohibitive practical problems with the approach and I dearly wanted to find something that said "Perpetual motion? Yeah, that's possible". I didn't though. Ha!

It was an interesting point you made above that a magnet will eventually lose its conserved energy after it is transfered into kinetic energy. I guess I was still enthralled by the "magical" floating paperclip from my youth and didn't stop to think that there might be a limit on how long the magnet could continue to cast its spells.

I still see potential in this idea in the form of using electromagnets but I am now trying to come up with a method of power supply that would be viable.

The Maglev trains could provide some more ideas here.

At the moment I am still in the realm of the early scientists (back when they were all philosphers) -- figuratively speaking -- and remain captivated with all the ideas.

Really appreciate you taking the time explain the things my glassed over eyes were staring through!

I really like the idea of this site. One problem: it's extremely difficult to use your text-entry box. The controls don't work, and I have to click at the end of a text line to give the box focus. This is a severe issue.

Anyway, back to cars. It's worth noting that the main limitations on car efficiency come from air friction, not ground friction. Cars (and other vehicles) are highly conservative in design; there are many exciting prototypes in funky aerodynamic shapes, which claim to deliver extraordinary fuel-efficiency.

For example, there's an electric car that (apparently) achieves the equivalent of 15,200 MPG (http://www.guardian.co.uk/uk/2005/jul/04/science.renewableenergy, http://www.primidi.com/2005/07/05.html#a1238).