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-Started with vector potential
-
-    (pic) Demonstrated why 𝐉ᵦ = ∇×𝐌
-
-(pic) Find magnetic field of a uniformly magnetized sphere
-
-    this development ended up converging with the sphere of constant surface charge
-
-
-(pic) Started with a reminder of displacement definition and origin.
-
-    (pic) This leads to an analogy with 𝐉ₜₒₜ = 𝐉𝒻 + 𝐉ᵦ
-
-    leads to very useful ∮𝐇⋅d𝐥 = 𝐈𝒻(s)
-
-Bit of an aside about how 𝐇 is easier to measure/control compared to 𝐁.
-
-(pic) An example of finding 𝐁 outside a thick rod.
-
-    actually didn't develop this, but just warned about that M has a
-    divergence at the edges, so 𝐇 is not so easy to find.
-
-Introduced linear materials
-
-    𝐌 = χₘ 𝐇
-
-    χₘ > 0 (paramagnetic)
-
-    χₘ < 0 (diamagnetic)
-
-    Example: an infinite solenoid carrying a surface current 𝐊 = K ϕ̂ filled
-    with material of susceptibility χₘ. Find 𝐁.
-
-        (pic) found 𝐇, then 𝐁, then bound and free 𝐊
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