River Cottage

So what is Perpetual motion?

I've always been a bit thick when it comes to physics but doesn't the fact that it's powered by magnets mean that it's not 'energy from nothing'? It's simply somehow converting magnetism into motion and then utilising the energy of the motion? Or am I totally out?

Me too Pippa, but perpetual motion is physically impossible as each iteration is minutely slowed by inertia and without a power boost of some sort then that slowing process eventually results in stoppage. Hence the inability to achieve perpetual motion without something coming along and giving it a boost. The simplest example is a child on a swing. Unless the adult comes along and gives it a push occasionally, the child eventually stops swinging and is stationary.

I`ve watched that Youtube video of the generator,its kick started by a battery,so i presume,its the magnets that keep pulling it around.

The comment by Jordan,that its not possible by the law of physics,

I presume your familiar with Earth magnets,think thats the right name,

The safetylamps we used underground could only be opened with a magnet,about 2in thick,and the width of the lamp around 3 1/2 ins,today an earth magnet the size of your thumb nail will do the job,them Orientals are clever chaps.

There are various substances which have different amounts of magnetism, so some magnets will be a lot stronger than others. There has been a lot of work done over recent years on magnets, superconductors, organic conductors and batteries. I suspect this earth magnet is a spin off from that work.

There must be some input into any machine to keep it going as there are things like friction, air resistance, gravity, losses between one form of energy (movement) to another (electicity for instance) to overcome.

The original poster never claimed "perpetual motion" (although they have got VERY close - with supercooled conductors)- just "Free energy" - just like the windmills and water wheels - and gravity engines ! 

Supercooled conductors are very good, but think of all the energy that has to be used to keep them supercooled. A lot of work has been carried out over the last few years on superconductors. One of the main aims of the work is to raise the temperature at which they become superconducting from near absolute zero to nearer room temperature. Not sure what the current record is, but may be possible to cool them with something like liquid carbon dioxide now rather than liquid nitrogen or oxygen.

That may all be very interesting alcy  

But the moment you start using them to do work - you're introducing a resistance which is going to kill perpetual motion - IMHO

UNlike the "free  energy machines" which don't claim to be "perpetual motion - just to perpetually keep moving - and probably allowing some power take off  - If some trickery of using natural resources like gravity or magnetism can be harnessed - then it's "Free energy" as per the original post - at least, as my understanding of it ! 

I think that's how I understood it too. If you can use electricity to produce magnetism, then why not magnetism to produce electricity? Or am I really just showing my thickness where physics is concerned?

Not at all - that's how cars produce electricity - moving wire in a magnetic field ! 

 In fact windmills and water turbines use it too to produce their versions of "free electricity"