# Tag Info

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There are two main reasons As temperature is decreased the voltage of a car battery decreases and it's internal resistance increases. This means the battery can supply less current. As temperature is decreased the viscosity of oil in the engine increases so the engine is harder to turn over. In the days before fuel injection there was a third factor ...

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The voltage differences you can get from thermocouples are usually in the range of $\mu$V per Kelvin for metals. In other materials this can be a bit higher but there is no material that can create thousands of Volts for a temperature difference between the heating and other parts of the building. For static electricity you need a few conditions coming ...

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In order to have the hot side remain hot, and the cold remain cold, while transmitting the electricity, ideally a substance is desired that conducts electricity well, but heat poorly. No. The two ends are assumed to be connected to heat sources or sinks that maintain a constant temperature at those nodes. Heat does flow well from one end to the other, ...

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The thermoelectric effect is the direct conversion of temperature differences to electric potential differences (Seebeck effect) and vice-versa (Peltier effect). When considering the electrical currents and heat fluxes involved, there is a size dependency, but such is not the case for the temperature differences and the electric potential differences ...

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The drift velocity is the net velocity of electrons in a certain direction under an applied field. The thermal velocity is has no net direction because it is randomly distributed and occurs in any metal at finite temperatures. Since the two velocities are different, it does not make any sense to say they are qualitatively equal, even though you may equate ...

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Micro black holes have been hypothesized in some large dimension string phenomenological models and are searched for in the experiments at the CERN LHC. The first approach to the decays was thermodynamic with Hawking radiation diminishing them rapidly. Their lifetimes are very short so there is no way to gather and contain them and experiment with feeding ...

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A Peltier module is not what you want. Some of the specs that I've seen require minimum currents of a few amps (≈2A for a small module), so unless you want to lug around even a small sealed Lead-acid battery with attendant wires, I'd think of something else. In fact, an electrical solution may not even be suitable. However, how about modifying a gas ...

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If you only want to heat the bit to help melt off ice from the screw and do not care about cooling the bit, then the Peltier device, which is a heat pump, is unnecessarily complicated and delicate. The most efficient way to heat something is through a resistive load (i.e. like in a toaster). There are a number options for making the heater, but a 100 Ohm, 1 ...

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The drift velocity of electrons in a metal is given by the equation $I=enAv_D$ where $I$ is the electric current in the metal wire, $n$ is the number of electron density, $A$ is the cross sectional area of the metal wire and $v_D$ is the drift velocity. From this we get $v_D= \frac{I}{enA}$ The thermal velocity is given by ...

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In a solid body the energy that we call heat is stored as vibrational motion of the atoms/molecules in the solid. When you place a hot solid in contact with a cold one the vibrating atoms in the hot solid bash into the more slowly vibrating atoms of the cold solid and transfer energy to them. You end up with the atoms in the hot body vibrating a bit less and ...

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