# Tag Info

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When charge accelerates, it radiates energy. The "prototypical scenario" illustating this is the uniformly accelerated point charge and the Larmor Formula (see Wikipedia page of this name) that quantifies the radiated power (both the non-relativistic and relativistic versions are given on the Wiki page). For an everyday example, you can think of a dipole ...

1

If you coat the inside, the metal will get hot and this heat will conduct into the building. If you coat the outside (assuming it remains clean…) you will never get hot to begin with. I think this means that case 2 will be better for you. I have often wondered about simply having a secondary roof with a standoff - in essence, a space where air can flow ...

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I am going to address only your second point: It seems that the maximum temperature an object could have is when: B) When the speed of the electrons nears the speed of light. In fact this does not impose any limit to temperature. When you add more and more heat to a body, its atoms and molecules move faster. At this stage, the electrons are not ...

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The entire premise of this question is false, neither do electrons orbit atoms with a well-defined speed, nor does this, in any way, correspond to the temperature, since that is a property of systems in thermal equilibrium, not of single particles. Also, whether the Planck length signifies really a shortest achievable wavelength is...debatable.

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First, a comment. Radiative heat transfer is oftentimes a non-factor for everyday objects encountered here on Earth. Radiative transfer is important for objects that can't exchange heat conductively or convectively, and for objects whose temperatures differ by a marked amount. That said, the rest of this answer will focus on radiative heat transfer. If ...

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A cold object heats up because at any given frequency it emits less energy and receives more energy than a hotter object. In other words, at any given frequency an object is just as efficient an emitter as it is an absorber (with a black body being the most efficient), but hot objects emit more radiation than cold objects do at each frequency, so the ...

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The premise is true if the object is in thermal equilibrium. See, for example, this Wikipedia article. Besides radiation, heat can be transferred by conduction and convection.

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If I understood well, your metal plate acts as a mirror. Seeing your own image in it is not surprising because what we call "IR" are actually photons. These photons have less energy than visible photons (IR means infra red, i.e. "energy below the energy of red photons") so you can't see them with your eyes. They are emitted by any hot object (that explains ...

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The method of modelling the chicken as a sphere, as mentioned on your other forum, might work something like this. Model the chicken as a sphere and use the heat equation, treating the surface as your boundary. The way to do this is discussed here. To obtain an approximate thermal diffusivity for a chicken you could use the equations you discovered above, ...

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There's no easy answer to your question as you don't define the nature of the gaz nor the nature of the cells. "Even if my understanding of the second law is incorrect, I don't understand why we can't extract heat energy from an object without a temperature gradient by placing it under certain conditions. For example, heat transfer via infrared radiation ...

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Bowlofred's answer is correct. You can get some insight by studying Feynman's Brownian ratchet - an attempt to get energy out of heat using statistical fluctuations (This also relates to your second point - that the Second Law is statistical in nature.) It consists of a tiny paddle wheel and a ratchet, and appears to be an example of a Maxwell's demon, ...

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There has been a new approach that you may consider. Your question involves the energy conversion between heat energy and Gibbs free energy. Since the two both are non- conserved quantities, the changes in heat energy and both Gibbs free energy can be divided into the two parts: one is the fluxes, the other one is the productions. For heat energy, $\delta Q$ ...

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The answer to this question primarily lies in the perception of what black-body radiation is. You must look at it not from the point of view of the source generating the radiation, but from the radiation as an object (or rather "gas") itself. What Plank's distribution talks of is the statistics of a collection of photons at equilibrium. So, in order to allow ...

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As it was done quickly, the mass of the mercury remained at room temperature for a short period of time, even as the thermometer itself (including the metal bulb) began to heat. I suppose it is possible that even though it is a tiny portion, the metal bulb expanded sufficiently so that the volume inside the bulb increased and the level of the mercury went ...

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If you work through the equations of a solar cell in detail, you find that the maximum possible efficiency of a solar cell is a function of the cell's own temperature and of the radiation brightness temperature of the light hitting it. If the two temperatures are the same, as they would be in your drawing, you find that the maximum possible efficiency is 0. ...

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"The gas would slowly radiate its heat through the glass to the ambient container housing the vacuum, and solar panels lining this surface could feasibly collect this energy." No. If we assume the gas inside and the cells outside are both at temperature $T$, then no (thermal) energy can be extracted. They will be in thermal equilibrium. Whatever ...

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"Bright light can never hurt your eyes" seems false to me… enough energy focused on the retina will cause damage, regardless of the wavelength. Otherwise you would not need to wear laser goggles… That aside, materials typically have certain ranges where they absorb light more strongly than others. There is no hard and fast rule for this, but if you google ...

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Uv goes thru glass, I thought that comment strange when I watched it. Laminated glass (which it could have been) would shield about 95% of the uv, I believe due to the resin interlayer.

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