Explaining Faraday's Law: Why ε=2∅/Δt?

Thread starter HelpMeh
Start date Apr 19, 2012
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Faradays law Law

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The equation ε=Δ∅/Δt represents the induced electromotive force (emf) in a coil due to a change in magnetic flux. When the plane of the coil is flipped, the magnetic flux changes from positive to negative, resulting in a total change of 2∅. This is because the change in flux is calculated as the difference between the final and initial flux values, which effectively doubles the absolute value. The discussion clarifies that the negative sign indicates a reversal in direction, reinforcing the concept of total change in flux. Understanding this principle is crucial for applying Faraday's Law in practical scenarios.

Apr 19, 2012

HelpMeh

Hi

Could someone explain why

ε=Δ∅/Δt

becomes 2∅/Δt?? i don't see how the change in magnetic flux is 2∅.

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Apr 19, 2012

BruceW

Science Advisor

the plane of the coil is flipped so that the normal to the plane becomes opposite. Therefore the flux is negative of what it was before, so the total change in flux is twice the absolute value of flux through the coil.

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