Direction of Electric Field in a Changing Magnetic Field

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SUMMARY

The discussion centers on the direction of the electric field induced by a decreasing magnetic field, as described by Lenz's Law. In a scenario where the magnetic field is directed out of the page and decreasing, the induced electric field at a point to the right of the region is confirmed to point towards the top of the page, contrary to the provided answer which states it points downwards. The reasoning involves applying Lenz's Law and the right-hand rule, leading to the conclusion that the induced current circulates anti-clockwise, aligning with the direction of the electric field.

PREREQUISITES
  • Lenz's Law
  • Right-Hand Rule for magnetic fields
  • Understanding of electromagnetic induction
  • Mathematical representation of Faraday's Law: ∇×E = -∂B/∂t
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  • Study the applications of Lenz's Law in electromagnetic systems
  • Explore the right-hand rule in various electromagnetic contexts
  • Investigate the implications of Faraday's Law on electric field generation
  • Learn about the behavior of induced currents in different geometries
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Physics students, educators, and professionals in electromagnetism, particularly those focusing on electromagnetic induction and its applications in circuits and fields.

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Homework Statement



In a circular region in the plane of paper, a magnetic field is directed out of the page and decreasing. What is the direction of the electric field at a point to the right of the region?

Homework Equations



Lenz's law

The Attempt at a Solution



Since the magnetic field is decreasing, Lenz's Law states the induced magnetic field will oppose this change, so the induced magnetic field will also point out of the page. So to the right of this region, the right hand rule says that the electric field should point towards the top of the page, but the answer in my key is to the bottom. Am I wrong?
 
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The magnetic field is out of the page and decreasing - this would correspond to a south pole facing the page and being drawn away ... so the page should have an induced north pole there, because it wants to pull it back.

Which would put the current circulating anti-clockwise.
Current follows the electric field - so you seem to be right.

You could also work it from ##\nabla\times\vec E = -\frac{\partial}{\partial t}\vec B##
 

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