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stfz
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Homework Statement
I'm trying to see the relationship between the negative sign (Lenz's Law) in Faraday's law. It states that EMF is equal to negative flux change. I understand how to use Lenz's Law to find direction of current and hence EMF, but I am not seeing the relation between the neg sign and the EMF directly, that is, I understand it qualitatively, but not quantitatively in the context of the formula.
Flux and voltage are both scalar quantities, and they measure different things. So how can I geometrically interpret the negative in the formula? What would that mean?
Homework Equations
[tex] V= -\frac{d\Phi}{dt}[/tex]
The Attempt at a Solution
If I draw up a diagram, and flux change is positive, then I know that EMF is negative in the loop. But how do I know which direction it is in? EMF could be measured both ways!
So I'm wondering whether or not the negative sign in Lenz's law simply serves a "qualitative" function, i.e. to let the reader know that it produces a current that opposes the flux change, rather than any computational significance? :P