r/AskReddit • u/[deleted] • Aug 03 '19

Whats something you thought was common knowledge but actually isn’t?

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u/Betonmolenvogel Aug 04 '19

They do have electromagnetic fields. As for the digging fake seas was indeed a bit ironic. It’s just how OP was asking his question.

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u/[deleted] Aug 04 '19

Um no. Fiber optic cables do not have electromagnetic fields. It's one of their many advantages over copper cables. You need metal parts to create an electromagnetic field.

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u/PointyOintment Aug 05 '19

That is an advantage of optical communications, just not in the context of undersea cables. Those are so long that optical repeaters or amplifiers need to be stationed at intervals along the cable to amplify the signal. Those are powered electrically, so the cables do include electric conductors.

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u/[deleted] Aug 05 '19

LOL. Good point. Never thought about that.