power cord directionality


IF power cords do indeed have preferred directionality, and one is inadvertently flipped for a few hours, does it "harm"it?
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On some cables the ground wire is only connected on one terminated end. It helps to reduce ground noise or hum. On a power cable that is grounded or has a ground plug it should not matter that much as long as both ends are terminated and your equipment that is using the cable is utilizing the ground. If it not using the ground then we might run into some ground noise issues because the signal is still there. If your piece of equipment does not have a ground ( like on a receiver) then it can cause ground loop hum. In this case the wire is not terminated or only terminated on one end. Also I have heard if you have a very sensitive system then the way the copper is extruded determines the direction of the signal. 
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uhhh... duh end wif duh prongs on it gits plugt innuh wol. duh uther end innuh yer lektronix.  

how yu gonna ree vurs it?


didn't you miss few "mmm....like...mm...you know...mmm...like..."
by any chance?
IE:  ALTERNATING CURRENTThat is the key word!  Current alternates direction.  Yes, DC power does exist, and transformers are DC to keep from blasting everything with a 60 cps hum, but interconnects and speaker wire?   NO!   Think about it.  Current for a 400 cps signal, for example, goes back and forth 400 times per second.  It does not flow like water.  The current driven magnetic force pushs the speaker out 400 times a second and pulls it in 400 times per second.  It does not push and rest.  Directional wiring for alternating currents, such as for fuses, speaker, and interconnect wires, is pure witchcraft, i.e. fantasy.   If you do not grasp this, I have some magical, one direction, magiquark driven fuses for sale.  Call 1-800 One Muon.