How can the unit of H and J be different?

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Maxwell's equation shows that the curl of H, represented as ∇×H, equals J plus additional terms. The unit of H is A/m, while J is measured in A/m², leading to confusion. The difference arises because taking the derivative of H introduces a length dimension in the denominator. This is similar to how velocity (m/s) and acceleration (m/s²) relate through differentiation. Understanding this relationship clarifies the unit discrepancy between H and J.
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Maxwell's equation is

∇×H=J + ...

but the unit of H is A/m while J's unit is A/m2

as quoted from wikipedia

how can it be possible?
 
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Tesla Gwon said:
Maxwell's equation is

∇×H=J + ...

but the unit of H is A/m while J's unit is A/m2

as quoted from wikipedia

how can it be possible?
You're taking the derivative of H, and this involves dividing by a length. The components of Curl(H) has terms like partial(H)/partial(x), so there is an additional length in the denominator. This is just like the fact that the units of velocity are m/s, while the units of acceleration (which is the time derivative of velocity) are m/s^2.
 
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i see ! thank you very much
 
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