Electrical vs Mechanical Energy

  • Thread starter JosephB
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Main Question or Discussion Point

I'm pretty new to physics. It has always fasinated me. I've had this idea floating around in my head for quite some time. Maybe someone could point me in the right direction.

An electric motor converts electrical energy into mechanical energy. An alternater converts mechanical energy into electrical energy. Is it possible to connect a battery to an electric motor, connect the electric motor to an alternater, connect the alternater to the battery and thus have a motor that would basically run itself? Would there be enough mechanical energy created to run the alternater and still do any work? Could the alternater provide enough electrical energy to keep the battery charged?

Thanks, Joe

Answers and Replies

No - what you are asking for here my friend, is free energy - this simply does not exist(according the the law of thermodynamics!) except for things like solar power and wind power etc - these are usually termed as 'free energy'.
Back to your idea:basically you'll have energy loss in the alternator and electric motor (losses in the form of heat and sound). Due to this power ( remeber power =E/T)loss accross your system, the alternator will not be able to charge the battery as fast at the battery supplies the electrc motor - read up on perpetual motion where lots of guys claim they've designed working systems close to that of your idea! very interesting!! hope this helps
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Note (for clarity): Harnessing wind or solar power does not violate the second law of thermodynamics.