Line charge creating induced emf and displacement current

AI Thread Summary
The discussion revolves around calculating the displacement current and magnetic flux in a scenario involving a time-varying line charge on a straight wire and an adjacent square wire loop. The line charge is defined as λ = λ0 exp(-βt), with λ0 as the initial charge and β as a constant. Participants express uncertainty about deriving the electric field from the time-varying charge and applying Faraday's Law to find the induced emf. Clarification is sought regarding the geometry of the setup, specifically the relationship between the wire's direction and the loop's orientation, as well as the definition of the distance "a." Visual aids are suggested to enhance understanding of the problem.
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Homework Statement


A long, straight wire has a line charge, λ, that varies in time according to: λ = λ0 exp(-βt). A square wire loop of dimension a is located adjacent to the wire at a distance of a from the wire. Calculate expressions for the displacement current at the center of the wire loop and the magnetic flux through the loop.

a = the side length of the square wire loop.
λ0 = the initial charge of the line charge at time t = 0
β = I assume some kind of constant. I haven't encountered this variable in a displacement current problem before.

Homework Equations


idisp = ε0 * dΦe/dt
ε = -dΦm/dt
Φm = ∫B ⋅ dA
Φe = ∫E ⋅ dA = qenc / ∈0
∫ E ⋅ dl = -dΦm / dt

The Attempt at a Solution


I'm pretty sure I can find an expression for the electric field first by integrating the equation for the time-varying charge, but I'm not sure how to set that up. I think I should integrate with respect to time and treat radius as a constant. From the electric field I can use Faraday's Law to find the emf, but again I'm unsure as to how exactly to set up the math.
 
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What is the juxtaposition between the wire direction vector and the normal to the loop? I.e if the wire vector is in the x direction, is the loop normal in the y or the z direction?

Is "a" the distance from the loop's center to the perpendicular distance to the wire, or is "a" the perpendicular distance from the closer collinear loop segment to the wire?

A picture would help immensely.
 
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