motor Crank ?
By reco369
@reco369 (273)
Philippines
July 14, 2011 10:09pm CST
Guyz i open this discussion for electric motor enthusiasts. Just want to
ask if a permanent magnet motor with coil as rotator, if you remove coil
and replace it with permanent magnet also, will the motor rotate forever?
Coz if the coil needs to pump with electricity to produce magnetism, why
not replace that lousy coils with strong neodymium magnets as rotator to
produce very strong magnetism which rotates the dynamo motor?
Heh What a weird idea but fellas can you have comment on this..really want
your comments.....waiting
1 response
@owlwings (43910)
• Cambridge, England
15 Jul 11
There are two main reasons why this will not work.
1) The moving coil uses a commutator to reverse the current in the coil during each rotation this ensures that the poles of the coil are always opposite in sign to the fixed poles of the magnet. If you replace the coil with a permanent magnet, the polarity cannot be changed and it could not even make one rotation.
2) Even if you were to devise a machine which somehow changed the polarity of the magnet, you would still have to put work INTO the machine to do this. Also, no machine is 100% efficient - there is always some power needed to overcome the resistance of the bearings and of air resistance (not to mention the power needed to make the machine do useful work).
