why copper wires are tin coated in electrical cables?
606036
First of all, copper si very good electricity conductor so, is commonly used in electrical installations, but it's coroded in free contact with oxigen an humidity which creates oxides (something like rust on iron). These oxides (unlike the iron rust) are very compact and they are practically waterproof protecting the copper material to be oxidazed further, but is very poor electricaly conductive. Instead, the tin material makes oxides by the same process, but they are very very thin (because of greater compactity)--order of microns, or thousent part of a milimeter-- and the electrical current can pass trough.\nDfriend :)
331010
Tin fibers are very strong and can be used like carbon fibers in epoxy to make very strong composites.  Tin whiskers can be used in electrical work (radio) as diodes.  These are pretty unusual.
463517
the external electric field creates an electric field in the copper. however, copper is a conductor so charge flows within the copper so that the net electric field is 0.
99453
It's been around for along time:\n\nTin (anglo-Saxon, tin, Latin stannum) is one of the earliest metals known and was used as a component of bronze from antiquity. Because of its hardening effect on copper, tin was used in bronze implements as early as 3,500 BC. Tin mining is believed to have started in Cornwall and Devon ( esp Dartmoor) in Classical times, and a thriving tin trade developed with the civilizations of the Mediterranean. However the pure metal was not used until about 600 BC.
676026
Wild guess here... a dihydrate of copper chloride.\n\nSecond guess would be copper sulfate, possibly from the manufacturing process.
89873
Best heat transfer should occur with a good thermal conductor like copper, to carry the absorbed heat away, coated with a thin heat-conducting layer of flat black, may be an oxide of copper.
975863
Connection? or disconnection...\n\nSemiconductors are not metals - nor do they intend to be.
878974
An example of a conductor (of presumably heat and electricity) are any metal, such as gold, silver, nickel, platinum, iron.\n\nAn example of an insulator is rubber.
237565
FIBER OPTICS IS USED ON LONGWIRES FROM CENTRAL OFFICE TO CENTRAL OFFICE !  WHERE COPPER WIRES ARE USED FOR DISTRIBUTION FROM THE CENTRAL OFFICE TO THE USER!\n\nFIBER OPTICS IS USED BY MAJOR COOPERATIONS IN CONNECTING THEIR SWITCH TO THE MAIN LINE.  AND ON CERTAIN LEASE LINES CONNECTIONS AGAIN BY MAJOR COOPERATIONS USING A WIDE BANDWITH WHICH TODAY IS USUALLY DIGITAL DATA, BUT CAN EASILY BE TELEVISION FEED! THRU LEASE LINES.\n\nFIBER OPTICS IS AT A MAJOR DATA TRANSMISSION LEVEL OR IN INDUSTRY IT IS USED WHERE MAGNETIC INFLUENCES LIKE WELDING IN SHIPBUILDING INTERFERE WITH DATA SO THEY USE FIBRE OPTICS EXCLUSIVELY ALMOST NO COPPER WIRE AROUND THE NUMERIC CONTROL DATA LINES IN THE AUTOMATIC WELDING AND CONTROLS FOR CUTTING STEEL AND WELDING SHIPS TOGETHER!\n\n\nTHATS ABOUT IT ALSO IN THE AIRFRAME BUILDING INDUSTRY!  WHERE MAGNETIC INFLUENCE MESSES UP THE NCR EQUIPMENT!\n\nHOPE THAT HELPS YOU OUR SOMEWHAT!\n\n\nHAVE A GOOD DAY!\n\n\nAPS
633356
http://www.connectworld.net/shielded-cables.html
347377
At the very basics it has to do with magnetic fields. When a conductor (ie copper wire) is move across (perpendicular to) a magnet-ic field it causes the electrons in the copper wire to move\n\nthis is very basic info and their are other ways like solar cells (due to electron excitment in a different manner)
233154
I believe your real question is whether a change in conductivity could be detected over time as an oxide coat forms.  Of course, copper wires (say in the windings of motors or transformers) are often insulated by a thin coat of perhaps varnish (for electrical reasons) and will not corode.\n\nHowever, if a wire is used to conduct high voltage or rapidly oscilating current and voltage, there can be a skin effect because electrons repel each other and would push themselves to the "skin" of the conductor.  Oxidation which actually removes some copper (reduces cross-section) and changes the resistance (oxides resist current more than pure copper) would have to reduce conductivity depending upon the extent of oxidation.  The effect should be greater in stranded wire with greater surface area.  That said, it may require lab quality instruments to detect any change which might be rather small.  An ohmeter passes nil current and uses DC (from an internal battery) and may detect little or no change which could become apparent under operating conditions within a sophisticated circuit.
979004
copper is a ductile metal, which means it can be drawn into wires easily, and is not naturally very brittle. however, by certain processes, it can be made brittle. for example, by heat strenthening that is, copper is heated to high temperatures and then suddenly colled by plunging it into water. continuously doing this can make the copper more brittle.
71861
Fiber optic cables offer two big advantages over traditional copper in a network:  they are immune to electromagntic interference, and they can run much much further than copper without needing repeaters.  The bigest two disadvantages to fiber are that they are more expensive, and that the standards are still evolving.\n\nBoth of those disadvantages are going away, though, meaning that I strongly believe fiber is going to completely replace copper eventually.  Right now, many companies are "future proofing" by running fiber along with copper in walls so that if they need to upgrade to fiber in the future, it is already part of thier structured network.  Also, major backbones, either running between campuses or even just between wings or floors of a building are now more and more fiber only, because it just makes sense when you're already paying so much money to set up the backbone.\n\nThe source below is a tutorial on my company's website giving more details about fiber.
627817
steel... electricity conducts more on an aluminum cable, steel also supports the strenght of cable thats why it is made into core....
157642
Firstly, the purer the water, the worse it is to use as a conductor. Mainly, the dissolved conductive elements we find in tapwater increase its conductivity, but are not as effective as say the ones found in saltwater. So, unless you wanted to spend the time and money to dissolve the copper, zinc, lead, and other conductive materials in water that could more easily be ducted into wire, it won't be a good idea.
878521
Copper. It is so brilliant