what is the shielding &what's the kinds of it?
919740
In general the shielding of a cable (or electronic cct.) is metallic covering to protect against undesired signals from outside which may affect the performance of the device or the system.\nShielding mainly used in communication cct's , tuners , alarm system cct's and any application may affect or disturbed by the signals in the neighbor.\nthere are many types of shielding depending on the application:for cables we may find the mesh shield , aluminum sheath shielding, and other. For electronic cct shielding it is usually a metallic enclosure containing the cct.\none other thing, that some applications or devices during normal operation generating a high frequency signals with high power ,these devices must be shielded to prevent these signals from spreading outside.\nat last : ANY SHIELD FOR ANY APPLICATION MUST BE CONNECTED TO EARTH (MUST BE GROUNDED PROPERLY).
24114
Try here: http://www.foils.org/basics.htm
1083080
You want the shield in the conduit.  Shield wires only get connected on one end.\nC
854950
In general, it should be small atoms, because smaller atoms have less electron orbitals. Also, in smaller atoms there are less electrons and this means that the shielding effect is lessened. Thus the negatively-charged electrons are closer to the positive nucleus, and the attraction is stronger.
948861
Ok, i am an electronics teacher, but it will be very lengthy and cumbersome to explain, because you have to go as deep as electrons and positive and negative charges, so i can advise you to go to www.wikipedia.com and you will find a satisfactory answer.
1036890
That would be E; nonmagnetic.  Any idiot could figure that out
935132
keep it far from electrodomestics\n\n:> peace\n.
319742
Shielded twisted-pair (STP) cable, combines the techniques of shielding and the twisting of wires to further protect against signal degradation. Each pair of wires is wrapped in a metallic foil. The four pairs of wires are then wrapped in an overall metallic braid or foil, usually 150-ohm cable. Specified for use in Ethernet network installations, STP reduces electrical noise both within the cable (pair-to-pair coupling, or crosstalk) and from outside the cable (EMI and RFI). Token Ring network topology uses STP.
269316
There are many types but all work on the principle that different semiconductors (i.e conducts electricity under certain conditions) placed together can turn on larger currents in another circuit.\nThe metals usually used are Germanium, Gallium, Asenide or compound of these including Silicon and Aluminium.\nYou might want to look at http://en.wikipedia.org/wiki/Transistor for more detailed info.
119494
What kind of "safety"?
181815
Well.. they are all the same material, the Shields have different colors for one reason.. to give you the ability to distinguish them!\n\nThe only difference between them all is the (Order) they come in .. the RJ45 which is the thing that is fixed to the end of the cable has "8" copper tiny little pins when you look at it from the back (where you can't see the hook) you start counting from the LEFT .. this means the very first pin on the left is numbered 1 and the last is numbererd 8 the pins (and accordingly) the cables who are responsible for the data transmission are pins (1,2,3, and 6) and it MUST go the same order on the other end in order to make the cable properly connective!\n\nThere are two different ways you can arrange the pairs in the cable\n\n1. normal arrange (any colors to be set exactly the same on both ends) and this sort of cable is used when you have a hub or a switch that will connect a group of computers all together.\n2. cross cable -- and this is used when you want to connect two computers directly using theirNIC's (network interface cards) as a back to back connection without the need of a hub or a switch and in this type of cables all you have to do is change the two ends cable order 1 on one end goes to 3 on the other end and 2 goes for 6 and you have a cross cable :-)
191363
What kind. More specific.. Please
146474
I checked out those links.  It looks like a bunch of BS to me.  (FWIW, I have a BS in Physics with 33 graduate hours in Physics and a Masters in Science Ed.)\n\nFirst, the facts:  Electromagnetic Fields (EMF) are produced whenever electric charges are in motion, i.e. in all electrical devices.  Light rays are one form of EMF's.  We already know how to protect against those: Wear sunblock.  \n\nBut the EMF's that we're talking about here are radio frequency EMF's, which are much lower on the spectrum, and thus have much less energy.  The EMF's that have caused concern in the medical field are Extremely Low Frequency radio waves such as those produced by power lines.  When electricity is moving down the lines, oscillating back and forth 60 times a second, it sends off these low frequency radio waves.  Some epidemiological studies have associated long term exposure to these ELF radio waves with childhood leukemia.  This is still controversial, however, and the US EPA has not issued any official position about EMF exposure.\nIn any event, with power lines we're talking about constant exposure to relatively high (1 mG) EMF's.  You wouldn't get that from your home computer unless you parked yourself within 4 inches of it for 24 hours a day.  Remember, EMF's drop off in intensity as the square of the distance, e.g. doubling your distance reduces them by a factor of four, tripling the distance reduces them by a factor of nine.\n\nAnyway, the only real way to shield something from low frequency EMF's is to completely enclose it in a metal box or wire mesh.  These things are essentially versions of what physicists call a Faraday Cage.  The idea is that the metallic condutors absorb the EMF's so they don't penetrate the cage.  Radio engineers protect sensitive radio equipment this way.  Security experts do the same thing the other way around.  Radios, TV's and even computers and electric typewriters produce minute radio waves that can be picked up by very sensitive receivers, so to prevent spies from finding out what's going on in sensitive government sites, they shield them in metallic conductors.\n\nThe device your links show clearly does not surround you, so it can't be effective in shielding from EMFs.  All the talk about sympathetic oscillations is true but meaningless.  Any piece of metal does that; that's how antennas work.  An antenna is just a piece of metal; when a vibrating EMF hits the antenna, the electons start to vibrate in synch with it.  IOW, you could get the same result as these devices claim by just wearing a piece of metal on your chest.  The claims about blood flow, "healthy energy states", etc. are just nonsense.
938575
Depends what you mean by electronic device. Only some circuits give of electromagnetic radiation - e.g. cell phones, unshielded power supplies.\n\nThe sorts of electromagnetic radiation given off by consumer electronics is safe. The only exception is cell phones. The latest advice is to avoid using a cell phone regularly for excessive periods without a headset - especially children.\n\nNo devices give off nuclear radiation (except smoke detectors)
1059635
computer nowadays have at least 2 types of protection..\n anti-virus protection and firewall protection...\n\nfor the antivirus u have to click on ur antivirus program and click disable..\n\nfor the firewall u have to go to start - control panel- and firewall.. then  disable it..
1088099
insulators ; conduction
1154190
radiation? do you hear yourself?\n\nit looses heat b/c it doesn't get enough energy to keep it warm!  a solar cover is a good way to create that needed energy as it uses the suns rays and not weighing down your electricity bill.