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Where is all this Energy comming from?

  1. Nov 18, 2004 #1


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    Where is all this Energy comming from???

    Im very new to physics and have one big question. Maybe I've got the wrong ideas here but ill ask this question anyway. Sorry if the information is wrong, either I'm not understanding it clearly or read it wrong off the internet.

    I read that "matter is energy bound together and stabalized" (photons, electrons, etc.). And that there is a quantized energy level that holds an electron to is nucleus (preventing for the electrons to speed into the nucleus), and that eletrons aren't "trapped" in their "shells" but have discrete energy levels that keep them in their own orbital, and that we measure this by the probablity of an electron being at a certain area of this orbital in a certain point in time. (Correct me if i'm wrong, it's pretty hard stuff to understand lol)

    Then I read about Infrared waves and radiation. At the atomic scale, when an atom or molecule has motion, such as vibration or rotation, it emits infrared waves at different frequencies (within the wavelenghts of Infrared).
    Then I put two and two together and remembered that the hotter a molecule (or atom? not sure) is, the more vibration and motion it has. And the cooler a molecule is, the slower it moves (Thermal radiation otherwise know as Infrared). Therefore creating different frequency's for us to assign "false" colour. Red is hot, blue cold.

    I think I'm at least on the right tract from here, like I'm said im new to this stuff. :surprised

    So my question is, knowing that Infrared is constantly emited by the constant energy of moving molecules in forms of waves. And knowing that atoms have stabalized and bound energy levels. How is there this constant emition of energy (such as Infrared) if atoms have bound and stablized energy levels? Doesn't the energy run out? Where is all this enegy comming from?

    I don't know if I made sense or even if that question is anwserable but it's been on my mind and I thought I would ask it. :rofl:
  2. jcsd
  3. Nov 18, 2004 #2


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    Thank you to anyone who helps me out with this. :smile:
  4. Nov 18, 2004 #3
    When heated, the thermal energy is used to excite an electron in the atom to a higher energy configuration (an energy eigenstate corresponding to a higher energy); this is an unstable configuration. The electron then dexcites to its usual energy level, and does so by emitting a photon (since electrons and photons couple), which is the infrared or light you see.

    Simple, huh?
  5. Nov 18, 2004 #4


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    Ah ok, i think i see what your saying. Heat is the source of energy that excites an electron, releasing photons in wavelenghts creating the Infrared.
    When it's cooled the electron returns back to it's eigenstate energy configuration?

    So heat can be a source of energy its self?
    So you can't have one without the other?

    Last edited: Nov 19, 2004
  6. Nov 18, 2004 #5
    Heat is not a good concept; thermal energy is better; even better still is kinetic energy. When an object posseses heat, we mean it actually has thermal energy, which means that it's constituent molecules/atoms are performing random motion, jiggling about, but staying put in average. If they stopped jiggling, the temperature of the object would be -273degrees C, or 0 Kelvin. That's why there is no temperature below 0K, because at 0K the atoms have stopped jiggling. There is no further stopping to be made.

    Heat is energy. You can't have one without the other, they are the same.
  7. Nov 19, 2004 #6


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    Got it, thnx
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