Why is there Unstable resistance in filaments?
364536
Tungsten filament resistance changes with temperature but the change is stable and predictable. The rule of thumb for filament resistance as a function of temperature is R = R20*(1 + 0.0045*(T-20)), where R20 is resistance at 20C (room temp) and T is temperature in deg C (ref. 1). Operating temperature in lamps ranges from 2500C to 3000C (ref. 2). Thus at operating temperature, resistance will increase by a factor of 12 to 14 compared to the room-temperature value. In older electronic equipment, incandescent lamps were occasionally used as (sort of) constant-current sources.\nBecause the thermal time constant of a typical filament is a tenth of a second or more, 60 Hz AC will cause a ripple in the resistance (and the brightness), but this is stable. It might be possible to have large resistance oscillations if the resistance was proportional to a power of the temperature, and there could be a runaway condition (rapid burnout) if the resistance decreased with increasing temperature.
676729
wood has very high resistance so the current through it ignored (its effect very small)
1172279
The anti matter is actually very unstable. It all got anhilited after reacting with the matter particles. The probability of an antiparticle  encountering a matter particle is very high because the matter is much much more compared to the antimatter, so probably most of the anti matter has already been 'burnt'.
21069
Photosensitive resistors (or Light Intensity / Light Dependant Resistors) vary according to the amount of light that falls on the actual resistor.  \n\nThe included source below expresses resistance as:\nResistance = 500 / (Light Intensity) Kohm\n\nI think this can vary with the particular LDR used though.
71035
Not 100% sure. But I think its because the air inside isn't moving. The air inside is stationary, while it is continuously circulating outside, which causes changes in the temperature. IMHO
59635
Elements with octet configuration are more stable because the last layer of electrons is complete, so it doesn't have empty spaces to be filled by other elements (not easily). It is not impossible, but hard and not likely to happen under normal conditions. Under special circumstances, I suppose they do mix, like your case with Xenon.
137603
Consider  one small part of the dancing string:\nelastic energy <==> kinetic energy.\nThe sum of both is mechanical energy.\nIt is supposed to be constant.\n\nOnly the friction of the air damps the oscillations.\nMechanical energy ==> (friction) heat\nThat's all foulks!
1063906
You're confusing resistance with pressure. If indeed there is a difference in voltage between A and B then there will be flow.\nThink of a tank filled with water held a few feet above another tank that has a pipe joining the two. Water will flow to the lower container thru the pipe. In this case the pipe has no resistance, which means water flows at maximum possible speed.\nIf both tanks are at the same level, then, sure, there will be no water flow. That's not how the problem was stated, however.
94961
Well, not everything obeys Ohm's Law (for example, diodes), so it's not really a law.  It is more of a definition of R (resistance) in the sense that IF a system obeys E = I/R then that system has a well-defined resistance, R.
471231
If the bundle diameter is the same and the individual wires are round in cross-section, then obviously the area of wire metal in the cross section is less in the bundle than in the solid wire so the bundle has a higher resistance. But let's say you mean that the bundle is enough larger in diameter that the metal areas of both cross sections are equal as assumed by answer 2. Suppose there are N strands in the bundle and the solid wire has a resistance R. Then each strand's resistance is N*R. Contrary to answer 2 (if I am reading it correctly), it makes no difference if the individual wires are connected side-by-side or not, as long as they are connected together at each end. Connecting them thus in parallel makes the bundle's resistance equal to R. Since the strands are identical in resistance and therefore carry the same current, the voltage at any distance along one strand is exactly the same as at the same distance along any other strand. Connect them together at that point and what happens? No change in current flow because no change in voltage, and therefore no change in resistance.
837767
Bingo!!! You got it...air resistance.  If you dropped them in a total vacuum, they would both fall at the same rate.
448129
Causes of resistance\n[edit]\n\nIn metals\n\nA metal consists of a lattice of atoms, each with a shell of electrons. This can also be known as positive ionic lattice. The outer electrons are free to dissociate from their parent atoms and travel through the lattice, creating a 'sea' of electrons, making the metal a conductor. When an electrical potential difference (a voltage) is applied across the metal, the electrons drift from one end of the conductor to the other under the influence of the electric field.\n\nIn a metal the thermal motion of ions is the primary source of scattering of electrons (due to destructive interference of free electron wave on non-correlating potentials of ions) - thus the prime cause of metal resistance. Imperfections of lattice also contribute into resistance, although their contribution in pure metals is negligible.\n\nThe larger the cross-sectional area of the conductor, the more electrons are available to carry the current, so the lower the resistance. The longer the conductor, the more scattering events occur in each electron's path through the material, so the higher the resistance. [1]\n[edit]\n\nIn semiconductors and insulators\n\nSemiconductors have properties that are part-way between those of metals and of insulators. A silicon boule has a grayish metallic sheen, like a metal, but is brittle, like glass. It is possible to manipulate the resistive properties of semiconductor materials by doping those materials with atomic elements, such as arsenic or boron, which create electrons or holes which can move across the material lattice.\n[edit]\n\nIn ionic liquids/electrolytes\n\nIn electrolytes, electrical conduction happens not by band electrons or holes, but by full atomic species (ions) traveling, each carrying an electrical charge. The resistivity of ionic liquids varies tremendously by the salt concentration - while distilled water is almost an insulator, salt water is a very efficient electrical conductor. In biological membranes, currents are carried by ionic salts. Small holes in the membranes, called ion channels, are selective to specific ions and determine the membrane resistance.\n[edit]\n\nResistance of various materials\nMaterial Resistivity, ρ\nohm-meter\nMetals 10 - 8\nSemiconductors variable\nElectrolytes variable\nInsulators 1016\n[edit]\n\nBand theory\nElectron energy levels in an insulator.\nElectron energy levels in an insulator.\n\nQuantum mechanics states that the energy of an electron in an atom cannot be any arbitrary value. Rather, there are fixed energy levels which the electrons can occupy, and values in between these levels are impossible. The energy levels are grouped into two bands: the valence band and the conduction band (the latter is generally above the former). Electrons in the conduction band may move freely throughout the substance in the presence of an electrical field.\n\nIn insulators and semiconductors, the atoms in the substance influence each other such that between the valence band and the conduction band, there exists a forbidden band of energy levels that the electrons simply cannot occupy. In order for a current to flow, a relatively large amount of energy must be furnished to an electron for it to leap across this forbidden gap and into the conduction band. Thus, large voltages yield relatively small currents.
816994
stall??? You mean lock up or crash or semophor locking, stack dump or another of the hideous issues...there are MANY THINGS TO DO...I will post separetely
1063404
I doubt this is the case because network wires are usually run in small bundles.  In theory this might be a problem if the ENTIRE wall was layered with them from top to bottom.  Sporadic shielded wiring runs wouldn't do much to disrupt cell signals.  It's more likely that the cause of your interferance is your buldings layer(s) of concrete or brick.
873969
The following is from Wikipedia:\n\n"In a normal conductor, an electrical current may be visualized as a fluid of electrons moving across a heavy ionic lattice. The electrons are constantly colliding with the ions in the lattice, and during each collision some of the energy carried by the current is absorbed by the lattice and converted into heat (which is essentially the vibrational kinetic energy of the lattice ions.) As a result, the energy carried by the current is constantly being dissipated. This is the phenomenon of electrical resistance."\n(See "superconductor")\n\nAs to length and disregarding superconductors, any unit length n of a material has the property of electrical resistance.  Since resistances in series add, a length 2n will have 2 times the resistance of a length n, etc.  Also see "resistance" in wikipedia, where rho is defined.
1144696
gravity and air resistance.
147150
The electricity to power all the lamps passes through all of the lamp filaments as opposed to each lamp drawing enough power for it's filament only. The lamps have more current going through each filament causing them to burn out faster so they must be made thicker and when 1 burns out, they all go out.