How is Angular Momentum Conserved in Electromagnetic Fields?

golfingboy07
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Question1: Discuss the conservation of angular momentum for a macroscopic system of sources and Electromagnetic fields in a uniform isotropic dispersionless medium of permittivity epsilon and permeability mu.
Question2: Show that the differential form of the conservation law is:

∂/∂t(Lfield + Lmech) + div(M) = 0

where L-field = μεx x (Ex H)

and M = T x x

T is the Maxwells stress tensor

I am wanting help with both these questions
1st question: Would like some help to get started such as a couple of bullet points
2nd question: Not sure where to start

Thanks

GM
 
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The derivation for linear momentum is in most textbooks. Just repeat it for rXP. I suggest you look at "Classical Electromagnetism" by Franklin, which shows when to use E,D,B,H.
 
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