Really Quick Maxwell Eqns Question

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The discussion centers on demonstrating that the magnetic flux density defined by Bx=A1 y, By=A2 x, and Bz=0 is compatible with Maxwell's equations only if A1 equals A2. The user notes that the divergence of B is zero regardless of the values of A1 and A2, but questions how to handle the current densities Jc and Jd. They consider the scenario where both current densities could be zero, leading to a static electric field and a curl of B that must also be zero, which implies A1 must equal A2. The conversation emphasizes the relationship between static fields and the conditions under which Maxwell's equations hold true.
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Homework Statement



Consider a magnetic flux density of the form:

Bx=A1 y
By=A2 x
Bz = 0

where A1 and A2 are constants. SHow that the field is fully compatible with maxwell's equations if and only if A1 = A2


Homework Equations





The Attempt at a Solution



SO i guess i just have to show divB = 0, which it does regardless of A1 and A2 being equal and curl B = mu0 (Jc + Jd). But what do i use for Jc and Jd here? Is it possible for them both to equal 0? I.e. for there not to be any electric field at all and just a pure B field? in which case curl B = 0 which leads to A1=A2. Is this possible?
 
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I ask because i know that in free space Jc = 0 but we still count Jd i.e. epsillon 0 dE/dt right?
 
anyone able to help with this? seems like an easy question...
 
yes, there can be an electric field, but if is static, i.e. not changing in time, then the curl of B must be zero (if Jc=0 too, of course).
 
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