How Does Lenz's Law Explain Current Flow in a Falling Bar Magnet Scenario?

AI Thread Summary
Lenz's Law explains that the induced electromotive force (emf) opposes the change causing it. In the scenario of a falling bar magnet through an aluminum pipe, as the north pole approaches, it induces a south pole in the pipe, causing current to flow clockwise. Once the magnet passes, the south pole moves away, leading to a decrease in magnetic flux, which induces a current that flows counterclockwise. This behavior illustrates the fundamental principle of Lenz's Law in electromagnetic induction. Understanding these current directions is crucial for grasping magnet and electromagnet theory.
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I'm stuck with Lenz's law, and questions involcing magnet/electromagnet theory

such as:
The diagram shows a bar magnet falling through an aluminum pipe. Electric currents are induced in the pipe immediately above and below the falling magnet. In which direction do these currents flow?

http://www.quizmebc.ca/images/exams/4000130.gif

Any help/explanations would be greatly appreciated.

Thanks
 
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Lenz's law states that the emf induced opposes the cause of its production. So when the north pole of the magnet approaches a cross-section of the pipe, the opposite pole, ie the magnetic south pole is formed when viewed from the north pole of the magnet, hence the current flows in the clockwise direction.

When the magnet passes that same point, the south pole is moving away from it, since electric flux is decreasing due to the south pole, the emf will try to maintain the flux in the same direction and hence when viewed from the southpole of the magnet, the magnetic south is formed in that cross section of the pipe, and hence, the current flows in the anti clock wise direction when viewed from the frame of the magnet

Sorry if I couldn't make it clearer, but tell me what part irks you and ill help you if I can.
 
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