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Eddy Currents/Back EMF (1 Viewer)
- Thread starter GaDaMIt
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back emf is induced when you have a motor... the faster the motor goes, the more emf it will induce to oppose the supplied emf...
eddy current exist when a metal conductor passes through a magnetic field, a eddy current like electrical current is generated to oppose the relative motion between the magnetic field and the conductor...
they use the similar principle, but occurs at different place...
eddy current exist when a metal conductor passes through a magnetic field, a eddy current like electrical current is generated to oppose the relative motion between the magnetic field and the conductor...
they use the similar principle, but occurs at different place...
airie
airie <3 avatars :)
They're fundamentally different - eddy currents are circulating induced CURRENTS, whereas EMF is the electromotive FORCE supposedly driving the charges around.
http://en.wikipedia.org/wiki/Eddy_current
http://en.wikipedia.org/wiki/Back_emf
Back emf pushes back against the current that produced it - Lenz's Law.
Eddy currents are circulating flows of electrons within a conductor that produce a magnetic field that opposes the magnetic field that produced it - Lenz's Law.
Back emf happens in any wire that passes through a magnetic field: motor, generator. The electrons are free to move up and down the wire and are not forced from side to side in the wire.
Eddy currents happens in conductors in changing magnetic fields (or moving in a magnetic field): iron core of a transformer, metallic disc moving through a magnetic field. Electrons are forced into a circle and do not flow through a wire or circuit.
Hope that helps.
http://en.wikipedia.org/wiki/Back_emf
Back emf pushes back against the current that produced it - Lenz's Law.
Eddy currents are circulating flows of electrons within a conductor that produce a magnetic field that opposes the magnetic field that produced it - Lenz's Law.
Back emf happens in any wire that passes through a magnetic field: motor, generator. The electrons are free to move up and down the wire and are not forced from side to side in the wire.
Eddy currents happens in conductors in changing magnetic fields (or moving in a magnetic field): iron core of a transformer, metallic disc moving through a magnetic field. Electrons are forced into a circle and do not flow through a wire or circuit.
Hope that helps.
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Hey are auroras emitted by excited charged particles like protons trapped in the Van Allen belt ?
Back EMF = voltage
Eddy current = current
When you have relatively movement between a conductor and a field, back emf is induced. Eddy currents are formed based on the back emf (which is based on the speed of movement) and the resistance of the circuit, ie. V=IR
Eddy current = current
When you have relatively movement between a conductor and a field, back emf is induced. Eddy currents are formed based on the back emf (which is based on the speed of movement) and the resistance of the circuit, ie. V=IR