Whats reverse electromagnetic force?

AI Thread Summary
Reverse electromagnetic force, often referred to as back EMF, occurs in coils or transformers when an alternating current (AC) is applied. The primary coil generates an AC current that creates a magnetic flux, which induces a current in the secondary coil. This induced current generates its own magnetic flux that opposes the primary flux, resulting in a reduction of input impedance in the primary. This phenomenon is crucial for understanding how transformers operate and reflects the load impedance back to the primary side. The explanation clarifies the concept effectively.
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hi

can you please tell me what is reverse electromagnetic force?

thankz!
 
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I believe that you are referring to "back EMF" that is generated in a coil or transformer.

http://en.wikipedia.org/wiki/Transformer

When you put an AC voltage across the primary of a transformer, that generates an AC (lagging) current in the primary. That AC current generates an AC magnetic flux, which couples to the secondary coil. That changing flux induces a current in the secondary coil, which generates its own flux in the core, and that secondary flux opposes the primary flux. So any current flowing in the secondary causes a reduction of input impedance in the primary (the so-called Back EMF, or reverse voltage due to the reflected load impedance).

Does that help?
 
ya that helps!
thankz!
 

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