Electricity is of two types... AC & DC... Will the flow of electrons in AC & DC vary? If electrons are really flowing, then the conducting wire no longer should be a stable metal... it becomes an ion... is that true?\n\nAlso, as I understand from my physics books, electricity travels at the speed of light. Let us say I have an electrical heater connected in a circuit. The heater consumes energy. Since the mass of electrons cannot change, then, I assume that the speed of flow of electrons in the circuit should reduce after it passes throught the heater... is this true? If not, then where is the heat energy produced by the electric heater coming from?
205638
DC (direct current) only flows in one direction.  AC (alternating current) is current which changes direction back and forth with a regular period.\n   The electrons really do flow.  If you look at the "drift", or physical motion of an individual electron, it is much slower than you might think.  In a 12-gauge copper wire carrying 20 Amps of current, the average speed of an electron is quite slow; about 1/250 of a mile per hour.  There's just so many electrons moving along so slowly that it adds up to a substantial current.\n   Why then, when you flip a switch, does the light turn on so quickly?  That's due to wave propagation, which is much faster.  Think of waves in the deep ocean; the waves can move quite quickly, but if you're swimming in it, you're not moving nearly so quickly.  You feel a slight up and down motion, but the wave may be propagating at 30 MPH.  The water itself is not flowing along across the surface at 30 MPH, but the wave is.\n    It is exactly the same with electrons.  While the wave is moving very quickly, the electrons themselves move very little.  In the wiring of your house carrying 20 Amps of AC current, the electrons are wiggling back and forth 60 times per second over a distance of about one thousandth of an inch.\n    However, the wave moves much much faster, when you flip the switch, the change in voltage travels along the wiring at very near the speed of light (it's slowed down about 30% below the speed of light by the plastic insulation on the wire).\n    With that prelude, to answer your questions:\n- the copper wire is not typically called an ion.  During current flow, an atom may hand its extra electron to the next copper atom, but it also gets an electron from the atom on the other side.  Thus, each atom always stays about neutral in charge.  This is described as the copper atoms forming a lattice through which the "sea" of electrons can freely flow.\n- a heater does not work by converting kinetic energy of electrons to heat quite the way you describe.  Instead, it uses the electrical energy available on the conductors of the power cord, which takes the form of electrostatic force of attraction which pushes electrons from the negative line to the positive line.  As an electron eneters the heating element from the negative line, it feels a strong force of attraction towards the other end of the heating element, which is connected to the positive line.  The electron accelerates due to this force, and speeds up somewhat, but it travels only a fraction of a millimeter before it collides with a microscopic defect in the lattice of the heating element, and decelerates and transfers its kinetic energy into vibration of the lattice of atoms of the heating element (i.e. into heat).  It then accelerates again, then hits another defect.\n   The main thing which distinguishes the metal of the heating element from the metal of the copper wires feeding them is that the heating element has a higher density of lattice defects (i.e. higher resistance).  An excellent analogy is American falls at Niagra, where the water approaches in a deep, broad stream moving relatively slowly at high potential (i.e. the negative copper wire), then tumbles down quickly under acceleration of gravity, losing potential, but hitting a bunch of rocks on the way down.  Hitting each rock slows the water down, and also transfers some heat to the rock, but after each impact the water accelerates again as it falls to the next rock.  Then, the water leaves at lower potential in another slow, deep stream (i.e. the positive copper wire).
530823
The entire reason that every house and business and car/truck has breaker boxes is because of resistance. Current flowing where it shouldn't, and causes somehting to heat up is because of resistance!\n\nComputers....same thing. Most circuit boards have relayes that will 'trip' if a short occurs, and usually this results in things getting overheated.......because of resistance.\n\nResistance is like friction for electrons. If you rub two sticks together they get hot (resistance)....same for electrons flowing thru a wire. The electrons 'bump' into various things as they go, and it gives rise to heat to put it simply.\n\nToasters rely on resistance to work. Ever look inside when one is on? Ever see the glowing wires in there?.....resistance causes the wires to heat and get red hot! This is what 'cooks' your toast.\n\nSame for an electric oven.......electric heating in your home.\n\nDoes this help?\n\nGood luck to you!\n\n:)
304055
good conductors are material with very tight atomic structure. Remember you are talking about electron flow here. they flow best and easies through material with very tight atomic make up like lead gold copper aluminum silver so forth. Most good conductors are non ferrous metals. This means If you heat them up to melting point they will not get red hot first, you will see very little color change in them from solid to liquid state.
371463
Three  terms you need to know are:\n\nVoltage- This is the "potential" to make current flow through \n                a wire.  (measured in volts)\nCurrent- This is the actual electrons or "electricity"  which \n               "flows" through the wire. (measured in amperes or amps)\nResistance- This is the quality of a substance which tends to \n                      allow or inhibit the flow of electricity.\n\nOne more term is power. This is measured in Watts and is \n given as 1 Watt=(1 volt)(1 amp)\n\nHere's how it works.  You put a voltage across a wire.\nYou decide the voltage.  It does not change.  The wire and bulb has "resistance" and only lets a certain amount or current flow.  The current flows through the bulb and lights the bulb.\n So both 100 watt bulbs and 40 watt bulbs have the same \n120v "voltage".  The difference  is that less current flows through the 40 watt bulb, so it is dimmer.\nRemember that power or "Watts" is current  times voltage.\nso lower wattage means lower current.\nThe question should be how much current does each bulb use.\nThe answer is: 100 watt-5/6 amp\n60 watt- 1/2 amp\n40 watt- 1/3 amp
42782
No it wouldn't travel faster than the speed of light.\n\nThe frequency has no effect on things whatsoever. I can only assume that you think think that a 60 hZ cycle means the electrons have to travel between the east and west coast and back again 60 times every second. That is not true. Eletricity doens't work by a literal flow of electrons but by the motion of electrons, which is not the same thing.\n\nWhen the currrent reverses diection the elctrons don't all fly back along the cable. Instead the motion reverses. Think the electrons like a column of marching soldiers a mile long. When the Seargent Major orders an about  face the line changes direction of movement but the lead soldier doesn't have to actually run a mile to the other end. All that happens is that the lead soldier changes.\n\nIn exactly the way, when the current changes the flow reverses and the 'terminal' electron becomes the lead and vice versa. Nothing actually runs from one coast to the other.
181781
Light is faster because electricity has to interact with the atoms it finds as it moves along a wire. Electricity is only a BIT slower than light, but you cannot tell the difference in real-life situations.
431181
1) metal is a good conductor of electricity, and when charges are placed inside a conductor, they tend to spread out so that there's an even charge distribution.  since the object inside the metal enclosure is surrounded by charge on all sides, the electric field vectors from the charged metal enclosure cancel out on the inside.  therefore, there is no electric field inside the metal enclosure.\n2) yes, it's true that electricity flows from regions of high voltage to regions of lower voltage.  but if you attach a negative terminal to a positive terminal without putting some electrically-powered devices in between, you'll end up frying your battery really fast.
276889
A generator produces a current by moving a wire through a magnetic field.  If you had an infinitely large magnetic field, you could move in one direction forever and produce a dc current.  However, it isn't practical to do that.\n\nInstead, you put a ball of wire inside a much smaller magnetic field and you spin it.  The ends of the wire have to be touching something to complete the circuit so electrons can flow.  At one part of the circle, the wire is moving left to right across the magnetic field and causes electrons to flow in one direction in the wire, in another part of the circle, the wire is moving from right to left and the electrons flow in the opposite direction.  This is what causes the current to alternate.\n\nSo, when converting motive energy into electricity, ac current is the easiest to produce.  This is like what is produced by a car's alternator or a hydro-electric plant.
354427
Some heating elements are live, and some are not. Wire heating elements (in some electric kettles) are live, so it is not a good idea to touch them or stick your finger in the water that they are heating! I will describe the other type of heating elements as "tube" type heating elements. This is the type you often find in ovens and in some electric kettles. This type has the live wire running down the centre of a metal tube, however there is an insulator inside the tube between the wire and the outer metal tube. These are safe to touch as long as there is no fault in the element and as long as you don't mind getting burnt!!\n\nThe other point to make is that one end of the element is "live" while the other end is "neutral", or very close to "earth" potential. So, for the wire elements, it depends where you touch it as to whether you will be electrocuted.
524340
Charge is difficult to explain without just saying how it interacts with other charge...\nBasically its a fundamental property of matter, like mass. The difference is, since charge comes in two types, positive and negative, in most large collections of matter, they cancel out and things are generally electrically neutral (have no charge). It responds to other charges through electromagnetism, much like masses affect each other through gravity, and is affected by electromagnetic fields created by currents, and magnetic fields also.\n\nCharge sits on a fundamental particle, or atom, or molecule, or larger particle. If that particle is in a collection of other particles, all of which are moving in the same direction, you have a current - a flow of charge. An ampére (or amp) is a unit meaning "one coloumb per second", or that at a point in a circuit where 1 amp is flowing, one coulomb of (positive) charge is passing per second. The coulomb is actually defined in terms of the ampere - it is the amount of charge that flows past a point in one second when the current is one amp.\n\nIn the example you've given, 240 C passes a point every five minutes, or every 300 seconds. So every second, (240/300) C/sec flows. This is the same as saying that 0.8 (=240/300) amps is "flowing" at that point. The matter is complicated by saying that current flows - it doesn't really, its a property of a stationary point in a circuit. The charge flows. If the rate of charge flow changes, so will the current, but saying that the current flows is a bit of a misnomer. But we're stuck with it.\n\nHope this helps.
457457
the majority of the lost time is not in the wire it is in the switch so you are going to get it wrong\n\nas for the speed in theory electricity flows at the speed of light but in actual use the resistance of the wire and the circuit slows it down but the speed is so great that unless you are talking milliseconds it is instantaneous
309319
It is the flow of electrons through a medium.  Electrons will flow when it is energetically favorable for them to do so.  For instance, a battery works by creating a potential difference (voltage) between two ends of a circuit.  Electrons flow from the area of high potential to the area of low potential.\n\nConductors, such as metals, are materials in which electrons can move freely, so very little potential difference is needed to create a current.  Semiconductors have a certain threshhold voltage that must be reached before electrons will flow.  Insulators do not allow electrons to flow, or at least not without massive voltages.
307811
Electricity is essentially  a flow of charges which is driven by the electric field.\nso u cant expect to have a cup full of charges(electricity)\nSo dont get out in a thunderstorm with a bowl in ur hand to catch some electricity!!!
623665
The points made by the previous responders are reasonable. In the context of communication, speed more often means bits per unit time, rather than physical speed which is distance per unit time. Electricity does travel very fast in the *latter sense*, close to the speed of light - but what is it about an electrical circuit which limits the number of bits which can be transmitted per second?\n\nSuppose you tried to send information by switching on and off the power to an electric fan being observed by someone else. It takes five or ten seconds for the fan to slow down or regain normal speed after it's been switched off or on, so it would be impossible to communicate much more than 3 or 4 bits per minute reliably using such a system. If you tried to do it faster there would be no change observable at the other end.\n\nThere's a similar limitation for any pair of copper wires. If L is the inductance and R the resistance, it takes a time roughly t ~ L/R for the current to drop at one end when the voltage has been switched off at the other end. The magnetic field surrounding the wires keeps the current going just like the momentum of the fan blades.\n\nThere's nothing much that can be done about this except for changing the structure of the cable. For example the pair of copper wires can be replaced by a coaxial cable in which one conductor forms a cylinder surrounding the other. The magnetic fields produced by the two currents tend to cancel which substantially reduces the inductance L, allowing a much faster (bits/second) speed.\n\nWhen most of the telephone network was implemented there was no reason to use coax since a pair of copper wires works fine for voice (audio frequencies = roughly 10K-100K bit/sec), although these will probably be upgraded if the phone companies are allowed to compete with the cable companies. \n\nFiber optic cable also has a very high bandwidth (bits/second) ... but your question is specifically about electricity.
504851
I will put it in the order that is easiest to understand.\n\nAmpere: the speed at which electrons pass through\n(1A = 1 coulomb/second, where 1 coulomb is 6.24x10^18 electrons)\n\nWatt: the speed at which work (in joules) is done\n(1W = 1Joule/second. A joule is the amount of work, in Newtons (if you've done physics) x meters,)\n\nVolt:  Watts per Ampere, or Joules per Coulomb\n\nOhm: The RESISTANCE, by Volts per Ampere.
91003
copper and aluminum are best electricity conductors. I would say lead, since it's one of the densiest material out there. Heat is caused by vibrating atoms, denser material means the atoms are closer, and it's melting point is low too. As soon as you touch it with a hot soldering iron, the heat transfers right away and melts it.
32742
The electric company generates (makes) electricty, which they send through wires. These wires go to every house. In some places, you can seem them on the street, but in most places they are underground.\n\nWhen you flip a switch, your are connecting the lightbulb to one of these wires. So electricity flows from the wire to the lightbulb. When you close the switch, you disconnect the 2 wires.\n\nThat is what happens. How electricty is made, and how lightbulbs and switches works is a bit more complicated, but for that I suggest Wikipedia:\n\nhttp://en.wikipedia.org/wiki/Electricity\n\nThe basic idea behind generating electricity though, is that you are freeing electrons from atoms, which then go to other atom/s that absorb them.