What is Faraday's Law of Induction?

AI Thread Summary
Faraday's Law of Induction explains how a changing magnetic flux through a loop induces an electromotive force (EMF) and current in that loop. The discussion highlights that the direction of the induced current opposes the change causing it, as stated by Lenz's Law. If the current in an outer wire decreases, the induced current in an inner wire will align in the same direction to counteract the reduction in magnetic flux. Understanding these principles clarifies the relationship between current direction and magnetic flux changes. The conversation concludes with a positive acknowledgment of the concept's clarity after discussion.
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Homework Statement



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Homework Equations



faraday's law of induction


The Attempt at a Solution


umm i don't really understand this concept:frown: so here's my attempt. the answer is C so is it because if you have a wire within a wire and the current of one wire is going one direction, the current of the other wire always goes the opposite direction?
 

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No that is not a good way to think about it. If the current in the outer wire were decreasing, then they would be going the same way. You have to think in terms of flux. Lenz's law says: "An induced current is always in such a direction as to oppose the motion or change causing it"

The cause of the induced current is the changing magnetic flux through the loop. The flux is increasing into the page, so the wire on the inside needs to produce a flux out of the page to resist the change.

If the wire on the outside had its current decreasing then there would be less flux into the page, so the inside wire would have to produce more flux into the page, and the currents would be in the same direction.
 
thxthx i understand it now ^^
 
dinhjeffrey said:
thxthx i understand it now ^^

Good! Lenz's law is very cool. Check out this video on Lenz's Law.

 
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oh cool my teacher showed us this in class too! lool
 
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