What is the induced current in a resistor due to a moving wire with current?

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The discussion centers on calculating the induced current in a resistor due to a moving wire with current. A rectangle circuit with a resistor is moving away from a long wire carrying current, and the problem involves determining the current in the resistor located at a distance r from the wire. The initial approach suggests using Faraday's Law, but it is recommended to apply the Blv law for simplicity, as it directly relates the induced voltage to the magnetic field and the motion of the circuit. The correct formula for the induced voltage is emf = Blv, considering the different lengths of the circuit that may induce varying voltages. The conversation highlights the importance of understanding the interaction between the moving circuit and the magnetic field generated by the current-carrying wire.
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Homework Statement


A rectangle circuit which has a resistor R and has a size l*w. The circuit is moving away from an infinite long wire which has a current i moving up along the wire with velocity v. Find the current moving in the resistor's side which far from the wire r. Here's the figure of the problem. http://imgur.com/RcAbgVN

Homework Equations


Maybe Faraday's Law? Like, Φ = ∫ B ⋅ dA and ε = -dλ/dt .

The Attempt at a Solution


I found that my answer is -μ0ilv/2πr. But I'm not sure about it.
 
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I get a different answer, involving all the given parameters.
When dealing with moving media such as this loop, use the Blv law rather than Faraday's law. The latter can lead to difficulties.
The Blv law simply states that the voltage induced across a wire (for example) of length l moving at speed v and at right angles to a B field is emf = Blv. In vector form, emf = B (l x v).

In this case you have two lengths inducing differing emf's. Hint: what happens if you connect two batteries of differing voltages + to + (or - to -)?
 
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