Induced EMF in a small volume of a conductor?

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SUMMARY

The discussion centers on the behavior of induced electromotive force (EMF) in a copper slab subjected to a changing magnetic field, as described by Faraday's and Lenz's laws. It establishes that the induced EMF is localized to the area where the magnetic field interacts with the conductor, leading to induced currents primarily in that region. The conversation also explores the relationship between the induced EMF and an external voltage source, concluding that they would be in series, affecting the net voltage in the circuit. Additionally, the presence of eddy currents and eddy voltage is confirmed as a consequence of the changing magnetic flux.

PREREQUISITES
  • Understanding of Faraday's Law of Electromagnetic Induction
  • Knowledge of Lenz's Law and its implications on induced currents
  • Familiarity with concepts of eddy currents and eddy voltage
  • Basic circuit theory, including series and parallel configurations
NEXT STEPS
  • Study the mathematical formulation of Faraday's Law and its applications
  • Explore the concept of eddy currents in conductive materials and their effects
  • Learn about the practical applications of induced EMF in electrical engineering
  • Investigate the behavior of circuits with both induced and external voltages
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Electrical engineers, physics students, and anyone interested in the principles of electromagnetism and their applications in circuits and materials.

PhiowPhi
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Assume we have the following copper slab, with volume ##V##, and introduced a magnetic field covering a small area of it like so:

RNC1wTP.png

There is change in magnetic flux(##\phi##) due to the magnetic field increasing/decreasing, and via Faraday & Len'z law of electromagnetism, there is an induced EMF(##- \epsilon ##) to oppose that change, and with the conductor's resistance(##r##) an induced current(##I##).

One thing that I'm struggling with, is knowing/understating where the induced EMF is bound to? Is the induced EMF all around the conductor like so:
HsN3nUn.png

Where if I placed a volt-meter anywhere on the top part (A) and the bottom part, the voltage would be the same any point there?
Or , is the induced EMF limited to the area the magnetic field interact's with like so:
7B8O3ho.png

The blue rectangle represents the magnetic field, and r, the resistance of the whole slab.
Likewise, will induced current be focused to that area the magnetic field interacts with, or the entire slab?

One thing I'd like to add, if we introduced and exterior Voltage source to the slab, with the induced EMF, would it be in series?
A5lteD6.png

The total voltage if they we're in a circuit, and they are connected to one another the net-voltage in the circuit would be:

##V_n## = ##V## - ##\epsilon## ?
 
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PhiowPhi said:
Assume we have the following copper slab, with volume VV, and introduced a magnetic field covering a small area of it like so:
If I understand you correct, that some magnetic changing flux, repesented by XXXXXXX, is induced perpendicular through the slab, you will get a circulating emf around the flux:

circulationemf ⋅ ds = dΨ/dt , Ψ is the flux , s is a surrounding path ( the edge of the blue rectangle ).

You will get Eddy-voltage and Eddy-current.
 
Hesch said:
You will get Eddy-voltage and Eddy-current.

If connected to a circuit it would be Eddy voltage & induced voltage(one via circuit and one via the surface of the conductor)?
Also, if there is current running through the conductor from a source(V+) it would be in series and oppose the applied voltage as diagramed in the last image?
 

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