Determine voltage from a conductor in magnetic field

AI Thread Summary
To determine the potential difference induced in a wire moving through a magnetic field, the relationship between the Lorentz force and induced electromotive force (EMF) is crucial. The equation EMF = l v ∧ B illustrates how motion through a magnetic field generates an induced voltage. This can also be linked to Faraday's law, where the induced EMF is equal to the rate of change of magnetic flux, expressed as EMF = dΦ/dt. A stationary loop can still experience induced EMF if a magnet approaches it, despite the loop's motion being parallel to the magnetic field. Understanding these concepts clarifies the connection between motion, magnetic fields, and induced electric fields.
BBruyne
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Hi,

I would like to know how to get the potential difference due to a constant local magnetic field acting on a wire moving at a constant speed perpendicular to the field. What is the link between F = q v ∧ B and the actual difference of potential in the circuit ? How to determine the induced electric field ? I have attached an image to illustrate it.

Thank you,

Bbruyne
 

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Thanks for the link, very nice website. I am learning Faraday's law and I am trying to link motional emf to his law. I do understand that a squared loop of wire of length l moving with a velocity v into a stationnary magnetic field B will experience a Lorentz force and this force will induce an emf. From emf = l v∧B, with a bit of manipulation, we arrive to emf = dΦ/dt. http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elevol.html#c3That means that if the loop of wire is not moving but we approach a magnet into the loop, we get an induced emf. How can we justify this with the initial idea emf = l v∧B. We could say that the loop is moving relatively to the magnet but, it is moving in a parallel direction to the magnetic field of the magnet, thus v∧B = 0.
 
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