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Q & A: Spinning magnets and perpetual motion

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Most recent answer: 01/02/2011
Q:
can a 12v generator be made by using magnets only eg: a to j in a circle: A north pole pointing out? b,c,d,e. north pole pointing into centre? F north pole pointing out? g,h,i,j. north pole pointing into centre? by doing that would it allow the magnets to spin on there own? and generate 12v power
- Steve
Ardlethan, NSW. Australia
A:
Hello Steve,
Sorry, but what you are describing is akin to a perpetual motion machine.   Many inventors have thought up very clever schemes but all have failed.   First of all, in order to generate a voltage with magnets you need a loop of wire that encloses a changing flux of magnetic field.  If the loop is connected to a resistive load, the back reaction force will tend to slow down the spinning magnet.   Inevitably, this back reaction as well as friction forces will absorb energy and slow the spinning magnets down.  

There is a fundamental fact:  'The First Law of Thermodynamics' or conservation of energy, that prevents such devices from working.   I refer you to a nice Wikipedia article on this subject:  

LeeH

(published on 01/01/2011)

Follow-Up #1: just a little tiny bit of perpetual motion?

Q:
Are nano or quantum perpetual motion machines are possible?
- Anonymous
A:
Nope, sorry. So far as we know the laws of statistical mechanics are universal.

Mike W.

(published on 01/02/2011)

Follow-up on this answer.