Direction of induced EMF in loop

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SUMMARY

The discussion centers on the direction of induced electromotive force (emf) in a loop as described by Faraday's and Lenz's laws. The participant correctly identifies that the current is increasing upwards, leading to a magnetic field directed into the page. However, they mistakenly conclude the induced emf's direction as counter-clockwise, which contradicts Lenz's law. The correct interpretation reveals that the induced emf should produce a magnetic field opposing the original field, resulting in a clockwise direction instead.

PREREQUISITES
  • Understanding of Faraday's Law of Induction
  • Familiarity with Lenz's Law
  • Knowledge of the Right-Hand Rule (RHR)
  • Basic concepts of magnetic fields and current direction
NEXT STEPS
  • Study the applications of Faraday's Law in electrical engineering
  • Explore advanced examples of Lenz's Law in circuit analysis
  • Learn about the Right-Hand Rule in different electromagnetic contexts
  • Investigate the relationship between current changes and induced emf in various loop configurations
USEFUL FOR

Students studying electromagnetism, physics educators, and anyone seeking to deepen their understanding of electromagnetic induction principles.

iharuyuki
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Homework Statement


upload_2015-4-14_14-46-44.png


Homework Equations



Faraday's and Lenz' law.

emf = -d(ф)/dt

The Attempt at a Solution


The current is increasing upwards during that time interval.
Thus, by Right-Hand-Rule, the magnetic field goes into the page at the loop.
Lenz' law says that the loop's induced emf will produce a magnetic field that opposes the field from the wire.
Thus a magnetic field in the opposite direction, out of page, would mean, by RHR, that the induced emf is counter-clockwise.

This is however not the answer. Which one of the above statements is flawed?

Thank you very much.
 
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