Physical limitations of electromagnetic induction

AI Thread Summary
The discussion centers on the physical limitations of electromagnetic induction in the context of building a small induction motor. While there is no theoretical limit to the induced electromotive force (emf) if the wire is resistance-less, practical limitations arise due to the resistance of real wires. Longer wires increase resistance, which can reduce current and subsequently affect the motor's output. The motor's speed remains constant, as it is determined by the AC frequency, but additional wire length may yield diminishing returns in torque. Overall, while wire length does impact performance, it may not be a significant concern for the motor's functionality.
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Hello.

I am making a small induction motor and have been wondering about it's limits. I have googled a lot and can't find a helpful answer.

Is there a maximum length of coil that a magnetic flux of specific strength can excite ?


Thank you,

Gary.
 
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There is no theoretical limit to induced emf from flux if your wire is resistance-less. Yours probably isn't, so, since a longer wire would have more resistance, which affects current, which in turn affects the motor's output, there probably are limits.

The speed of the motor probably wouldn't change, as that is controlled by the frequency of the AC supplied to it. Instead, you might get less additional torque for additional length, if you use an extremely long wire. I wouldn't worry about it too much, though.
 
Thank you Livect.
 
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