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The temperature is not measured in the sense of using a thermometer. Instead it is calculated from the velocities of the particles in the trap. Temperature is related to the velocity distribution by the Maxwell-Boltzmann equation. Under normal circumstances we are usually starting from a known temperature and calculating the velocity distribution. However ...


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Ohm's law assumes the temperature remains constant. An Ohmic conductor is one in which the current flowing through it is proportional to the voltage applied across it. A non-ohmic conductor is one in which the voltage and current are not linear. A) The resistance of most conductors increases as the temperature increases, however being ohmic and not ohmic ...


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It is the mass of material more than the thickness that determines the stopping power (which incidentally is a function of energy - so you can't simply state "40 cm reduces gamma flux one billion times" without specifying the energy). Lead has a positive coefficient of thermal expansion - so the same amount of lead will become slightly thinner at colder ...


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Your idea does not seem to work if you have two particles at different temperatures. Assume you "stop" one of them but not the other. Then does the time slows down for only one particle and not the other? or how would you explain that?


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Any "system/object" can be in a thermal state and thus will be well described by concepts such as temperature. Talking about things in thermodynamic terms such as temperature express a degree of personal ignorance about the system, in which case you talk about an average or expectation of certain general properties (such as overall energy etc). As an ...


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A small system coupled to a temperature bath will have a well defined temperature (the temperature of the temperature bath), if you do not disturb it out of equilibrium. If a single, isolated particle is considered, things are not that tricky either. You can always consistently assume a temperature of zero (but you gain nothing by doing so). But a small ...


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Wind chill is really due to two things: 1) colder air moves across the surface of your skin, replacing the air you heated with your body: this in essence takes away the blanket of warm air you keep making for yourself. 2) As your body loses moisture through evaporation, there is a humidity gradient of stagnant vapor around your body. The higher the ...


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You can pump heat from cold objects to hot objects if you pay some more energy (that's what your refrigerator is doing) and that doesn't violate second law of thermodynamics. You should note as you heat object, its thermal radiation will increase. Intensity (that is power per unit surface area) of thermal radiation is proportional to $T^4$ so when the ...


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Assuming we can treat the air in the room as an ideal gas, it will obey the ideal gas equation of state: $$ PV = nRT \tag{1} $$ where $n$ is the number of moles of the gas. The question tells us that the pressure is constant, and obviously the volume of the room is constant, so the only things that can vary are $T$ and $n$. The question tells us that $T$ ...


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You are way overthinking this. First, you can start with radiative cooling, but that's not the dominant process. At 65 C, in your workshop, convection cooling is the big dog. The total effect will depend on the shape and size of your container, how good a thermal insulator (or conductor, if you prefer) and even details like airflow. Without knowing these, ...


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I hope someone with more knowledge will pop into thread, but here is my education. There might be number of ways to measure such low temperatures. One I find fascinating is starting with material, namely Bose-Einstein condensate. Reference is this one: Cooling Bose-Einstein Condensates Below 500 Picokelvin, Leanhardt et al. Science, 12 September 2003. ...


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You are confusing time with the flow of time. Time is just a coordinate like the spatial coordinates, that is we label spacetime points with four coordinates $(t, x, y, z)$. Indeed, in relativity (both flavours) the time and spatial coordinates get mixed up so different observers will disagree about what is time and what is space. But the obvious thing ...


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You will get most likely get uneven heating that is hard to reproduce - so I would say "no, that is not a good approach". Using a thermal bath like @BySymmetry suggested is much better - or wrap some resistive wire around it and run a known current through it for a known time. The key to good experiments is control and repeatability - your open fire solution ...



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