Recent content by erty

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    Probability and statistical mechanics

    (I didn't know where to put this one, so somebody will eventually move it, I predict...) This is a absolute newbie-question, so don't be evil! Why does statistical mechanics deal with probabilities? ASAIK, statistical mechanics is built on classical mechanics, where it is possible to predict...
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    Expansion of ideal gas into a vacuum

    Well, that's the problem. I consider the box with the gas to be my system and everything else to be the surroundings/universe. But what if I turn it the other way around? If I consider everything but the box to be my system, and I pull up the partition, then I've applied work on the...
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    Expansion of ideal gas into a vacuum

    This is Joule's experiment. He found out that the internal energy U of an ideal gas only depends on the temperature.
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    Expansion of ideal gas into a vacuum

    I have a box divided by a partition. On one side I have n mole ideal gas, on the other side there's vacuum. If I remove the partition the ideal gas will expand into the vacuum. Since the box is adiabatic and no work is applied to or by the gas, \Delta U = 0. But what about the work used...
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    Understanding of irreversibility

    Ok, thanks. Just had to be sure.
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    Understanding of irreversibility

    The thermodynamic explanation of irreversibility - does it include the microscopic view of a process, i.e. the expansion of a ideal gas (the random movement of the molecules) or the melting of an ice cube? Or is it only defined within the macroscopic world?
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    Is there a relationship between the energy and mass of photons?

    Yes, I stand corrected. I changed "a photon/particle" to photons/particles, but forgot to correct the rest. Then how do I validate hf = mc^2, if it can't be applied to something like photons: they do have energy, but not any mass. Does this have something to do with the wave/particle duality...
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    Is there a relationship between the energy and mass of photons?

    These are some of the very fundamental things about the wave/particle-duality, I do not understand: 1) Do photons have a mass? 2) Do particles have a frequency? E = hf , how do I interpret this? 3) E = mc^2 and E = hf. I've seen these two equations combined into mc^2 = hf, indicating that...
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    The Photoelectric effect and classical physics

    I figured it out. Thanks, everybody!
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    The Photoelectric effect and classical physics

    Why can't waves have discrete values (E = hf applies to particles?)?
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    The Photoelectric effect and classical physics

    Very good explanation. I'll dig into the physics stuff now that turdferguson and ZapperZ gave me some words to look up. Actually... no. I'm still in high school (or rather, the European equivalent) and this is my first year with physics. We're learning about waves at the moment, but this is...
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    The Photoelectric effect and classical physics

    Hmm, I don't know anyting about it. Could you list a couple of words, then I'll try to look them up or google them
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    The Photoelectric effect and classical physics

    The Photoelectric effect and "classical physics" The kinetic energy of the ejected electrons predicted by the classical physics should be related to the intensity of the light. According to experimental results, the kinetic energy of the electrons is proportional to the frequencies of the...
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    Explaining the Immiscibility of Oil and Water: A Thermodynamic Perspective

    @ definition of mixing I apologize for the confuzzlement. I did not know the distinction between the physical definition of mixing and the ... well, cook book's definition. This started when I mixed (oops) lemon juice and olive oil for a salad dressing, and the immiscibility thing made me...
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    Explaining the Immiscibility of Oil and Water: A Thermodynamic Perspective

    Many thanks to both of you. Now I do think I understand it, thanks for clarifying it!
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