Why are NTC thermistors non ohmic?
928307
Any temperature-sensing device whose resistance is a function of temperature is inherently nonohmic; i.e., does not display a constant resistance with varied current flow or varied applied voltage. This is due to the fact that current flow will cause the device to heat and do its job which is to change resistance. An NTC device could conceivably "run away" with a constant applied voltage; as current increases it heats up and its resistance goes down resulting in further current increase. Conversely, a PTC device could conceivably run away with a constant applied current; as it heats up its resistance increases resulting in a higher voltage drop across it, which produces more heating, etc. For this reason, when using a thermistor it is a good idea to measure its resistance with a very sensitive (low sensing voltage and current) ohmmeter to minimize spurious heat input.
263946
Have each page work on the same princable as the bi-metallic thermometer.  Try to find two materials the expand differently than eachother because of heat, or you could use humidity to expand one material more than the other. You could probably find some material that contracts (or expands) when an electrical current passes through it. place a strip of this along the top and bottom of each page. Thats all i can think of right now.\nCool question by the way.
898015
Nominal= 36ohms\nTolerance=5% \nMultiply nominal by .05 , then add that figure to nominal for Max,.subtract it from nominal for Min.,,and study your ohm's LAW!! ;-)=
948174
Of course. \nThe actual junction of an N type and P type is what prevents conduction when reverse biased.
606031
It's O.K. to stipulate there's no resistance - but not that the system can reach a static equilibrium state with no energy dissipation at all. The two assumptions are incompatible.\n\nIn the absence of resistance, the inductance, which can never be exactly zero even for a straight wire, would limit the current and also cause its direction to oscillate back and forth between the two capacitors until exactly 1/2 the original energy is lost through EM radiation. \n\nIf somehow there were no radiation, the system would keep oscillating forever with 1/2 the original energy being held in the magnetic field at the moment in each cycle when the capacitors were each exactly half charged. The rest of the time the capacitors would hold between 50% and 100% of the original energy.
332623
Maybe you could use its electrical resistance. But it wouldn't be easy as I suspect the temp coeff of the resitance is small.
881673
The non rechargeable batteries the chemical reaction is not reversible. U are lucky that it didn't blow up.
827050
Yupp... but unfortunately is a hardcopy on my desk. Perhaps you may straight to tell us what\n\n1. You are designing from HT to Transformer 11kV / 415V\n2. You are designinig from Transformer to LV ??\n3. What is the kVA of the transfomer?
249911
You wouldn't want a conductor for a heating coil, conductors aren't supposed to heat. You would want a resistor that would generate heat but still conduct the electricity needed. Nichrome Wire is generally considered the best and most common heating element.
27798
NiCads in general electronic applications are typically designed to NOT get hot, since the heat destroys the NiCad battery, can damage electronics and causes lawsuits when users get burned from the hot battery.  Some devices like radio-controlled cars are high-drain applications that generate a lot of heat, so the batteries for these devices are designed for their specific use.\n\nBatteries get hot when they charge due to the high current going into them.  The faster they charge, typically the hotter they get.  When the battery discharges during use, the same thing happens, the battery gets hotter as more current is drawn from the battery.  \n\nWithout knowing anything else, my guess is that high current draw from the battery cells is causing them to heat up.  This can be due to a defective battery, a battery not designed for the way you are using it or your modification damaged the battery or is otherwise causing excessive current drain.\n\nAlso, increasing the supply voltage can drive more current through the device, so it may just be that the higher voltage is drawing more current.\n\nI’m not sure how the device is shutting down, so I can’t say why it’s doing that.  Note that the voltage at which a device stops working is the voltage seen by the device itself.  If you remove the battery from the device and measure the voltage, you will get a different voltage than if you measure the voltage at the precise moment the device shuts down.  This is especially true for high current drain applications, which appears to be what’s happening with your batteries. \n\nPlacing the NiCad’s in the freezer won't help.  They’ll have to warm up to work properly anyway.
977787
Are you asking about thermal conductivity or specific heat?\nAnd why are you not doing the research you should be doing:\nhttp://www.engineeringtoolbox.com/specific-heat-metals-d_152.html\nhttp://www.engineeringtoolbox.com/thermal-conductivity-metals-d_858.html
672976
Are you certain it's not a temperature effect?  Most of the unrechargeable batteries I'm familiar with do have decreased power output at low (like around 40 F or less) temperatures.  I can't think of why a lower ambient pressure would cause the low power.
509223
Something else in the pocket made contact with both terminals, causing the battery to pass current and generating heat.  I did this once by tossing a 9V that I thought was discharged into my pants pocket where I have my office keys.  The keys completed the circuit from the positive to the negative terminals, and I shortly noticed the heat.
277145
http://www.nphheaters.com/products/thermocouples/thermocouples_int_codes.html\n\ntry it..
908047
Yeah is it ACPI compatible? That might be why it dosen't turn off in hibernation. Check www.acpi.info for more information.\n\nIf they are not then you will have to cut the current to them manually.
82587
You guys are both right--good answers.  Junction temperature also can affect the voltage drop.
1101939
A thermocuple might be the one you seek. \n\nThe seebeck effect on thermocouple uses this theory, as there are two different material soldered together to make a single V or U shaped bar, there is a point where those two metals met. When we heat that point, the heat will move the electron, and since one metal has different coefficient than the other, so the electron will move from one metal to the other, thus an electric current will be created.\n\nPeltier effect, uses the vice versa theory, thus if we put electrical current through that thermocouple, then the thermocouple will need to absorb heat from it surroundings, thus, it will lower the ambient temperature.\n\nI haven't got any clue on how effective does this "refrigerant" work, but I think It might, might, might, work..