Name the force

[alan2here]

Whats the name of the force that moves an electrically conductive metal ring inside a coil of electricity conducive wire forward when the wire has electricity flowing though it?

 

I know it is due to eddy currents and induced magnetism and it is like the opposite of lenz law (like reversing a motor gets a generator) but not what it is called.

 

I also though one could make a motor like this, with a wheel with washers around the outside and a coil that the washers moved though? There would unfortunately be collision conflicts between whatever was holding the washers in place and the coil.

 

Leading me onto my next conclusion which is that a torus of metal may be better?

[ydoaPs]

Magnetic force?

[swansont]

There is no opposite of Lenz's law. That tells you the direction of the current flow when the field changes, and Faraday's law tells you that the current flows in the first place (technically Faraday's law does tell you the sign, but the two are usually treated as separate concepts)

[alan2here]

http://video.google.co.uk/videoplay?docid=-5275112434762210941&q=Physics+for+Future+Presidents&total=66&start=10&num=10&so=0&type=search&plindex=5

goto 56:24 (thats when it happens probably best to start a little before the actual event). He is demonstrating the force.

[swansont]

Magnetic force, just as yourdad said. The jumping comes about because of Faraday's law.

[alan2here]

Thanks, I thought maybe there would be a name for it as it comes about where there is only one electro-magnet and one item that would not normally intract with magnets in any way other than as decribed by lenz law

[swansont]

I suppose one might call it the inductive force, because it's induced magnetism.