1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Electromagnetic radiation

  1. Apr 10, 2012 #1
    I recently read an article online stating that electromagnetic radiation is 'a form of energy emitted and absorbed by charged particles'.

    This isn't always correct, is it? I mean, I know that charged particles that are accelerating can emit bremsstrahlung and synchrotron radiation, but my own body will emit thermal infra-red, and I'm not made up of charged particles. Also, as I understand it, an atom can emit or absorb e-m radiation simply by electron transitions between energy levels; the atom is still neutral (although it could be in an excited state.)

    Am I correct, or hopelessly confused?


  2. jcsd
  3. Apr 10, 2012 #2


    User Avatar
    Science Advisor
    Homework Helper

    Hi Paul! :smile:
    but that is emission by charged particles, isn't it? :confused:
  4. Apr 10, 2012 #3
    :rofl: Yes, you're right of course...brain-freeze moment on my part! No further replies necessary!
  5. Apr 11, 2012 #4
    Basically charges affects other charge solely via EMF (photons).

  6. Apr 11, 2012 #5


    User Avatar
    Science Advisor

    Electromagnetic radiation also comes from annihilation of particles, irregardless of charge. I suppose an uncharged black hole also emits EM radiation.
  7. Apr 11, 2012 #6
    In the annihilation of particles charge is conserved and as far as I know Electromagnetic radiation is still created by Charge (electrons and/or quarks). In a black EM radiation is, as far as I know, created by Charges and escapes the event horizon due to virtual charged particle annihilation...


  8. Apr 12, 2012 #7


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    In the case of thermal radiation from your own body, it would mostly be a result of internal vibrations in polar molecules, such as H2O.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook