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The relation between vector magnetic potential and current density is given by ______

The relation between vector magnetic potential and current density is given by ______ Correct Answer ∇2 A=-μJ

Magnetic Flux density B is expressed as B=∇×A Taking curl on both sides, we get ∇×B=∇×(∇×A ) = ( ∇.A)∇-(∇.∇)A From Maxwell’s equation, ∇.B=0 =>∇.A=0 ⇨ ∇×B= -∇2 A and B= μH , ∇×H=J ⇨ ∇×μH= -∇2A ⇨ ∇2 A=-μJ.

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