a really hard one here. would appreciate help on how to do this question:(adsbygoogle = window.adsbygoogle || []).push({});

a physical system is governed by the following:

curl E = [tex]-\frac{\partial B}{\partial t}[/tex],

div B = 0,

curl B = J + [tex]\frac{\partial E}{\partial t}[/tex],

div E = [tex]\rho[/tex]

where t = time, and time derivatives commute with [tex]\nabla[/tex]

............................................

how could you show that [tex]\frac{\partial p}{\partial t}[/tex] + div J = 0

............................................

when [tex]\rho = 0[/tex] and J = 0 everywhere how can you show that:

[tex]\nabla^2E - \frac{\partial^2E}{\partial t^2}[/tex] = 0

and

[tex]\nabla^2B - \frac{\partial^2B}{\partial t^2}[/tex] = 0

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# Homework Help: Particularly hard question on a physical system

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