A metal rod moving thru a magnetic field

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SUMMARY

A metal rod moving through a homogeneous magnetic field generates a voltage across its ends, despite the magnetic flux remaining constant. This phenomenon is explained by the equation W/Q = vBq*L/q, where L represents the rod's length. The confusion arises from the interpretation of Faraday's law of induction, which states that induced voltage is proportional to the rate of change of magnetic flux. The rod's motion leads to a current that flows in a direction that opposes the change, as described by Lenz's law, resulting in a constant speed rather than a stop.

PREREQUISITES
  • Understanding of Faraday's law of induction
  • Knowledge of Lenz's law and its implications
  • Familiarity with electromagnetic principles, particularly in relation to motion
  • Basic grasp of circuit theory and current direction
NEXT STEPS
  • Study the principles of Faraday's law of induction in detail
  • Explore Lenz's law and its applications in electromagnetic systems
  • Investigate the relationship between magnetic fields and induced currents
  • Review the dynamics of motion in electromagnetic contexts, focusing on constant velocity scenarios
USEFUL FOR

Students preparing for exams in physics, particularly those focusing on electromagnetism, as well as educators and anyone seeking to deepen their understanding of electromagnetic induction and its applications.

Nikitin
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Hi. A metal rod is moving thru a homogeneous magnetic field, standing 90 degrees upon it and the movement direction.

Supposedly there is a voltage between the two ends of the rod due to the moving. But why? The magnetic flux doesn't change!

I know that the voltage is supposed to be W/Q = vBq*L/q where L is the length of the rod, but still isn't faraday's law of induction (generated voltage = flux change) broken?

See the uploaded picture for further info
 

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Check the picture inside the attached word-file.

A rod lies frictionless on two rails. When the circuit is opened the rod starts moving to the right by itself. What is the direction of the current inside the circuit?

I say it's against the clock, and the magnetic field tries to counteract it and change the direction of the current. The book says it's with the clock, and the magnetic field tries to counteract it.

Why am I wrong?

Additionally, the book claims that rod will eventually get a constant speed to the right. Why? That means the magnetic flux is constantly increasing, and according to Lenz's rule the rod should eventually STOP, not keep going!
 

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Help? I've got exams on Tuesday, I really need help
 

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