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We learn that EM waves cause the electrons in a conductor to move around. For example, air to ground radar shows the ocean as having few returns compared to land. Water molecules absorb the energy. Doesn't the induced motion of electrons in the metal in chaotic eddy currents dissipate the energy? I read this:

https://www.researchgate.net/post/Why-are-Microwaves-reflected-by-metals

but was not enlightened.

aquagremlin
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1 Answers1

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Because metals are electrically conductive, an incoming radar pulse induces a current to flow in the surface of the metal. That current flow then radiates a replica of the original wave, moving in the opposite direction.

niels nielsen
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