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Homework Help: Which of the following will produce Electromagnetic radiation?

  1. Jun 20, 2012 #1
    1. The problem statement, all variables and given/known data
    Which of the following will produce Electromagnetic radiation? Explain Your answers.
    a) Alternating current in a TV transmitter
    b) The cord of a vacuum cleaner while it is being used
    c) The circuit of a battery operated CD player
    d) A positively charged particle travelling around a cyclotron
    e) The wire connecting a DC light globe to a power pack

    2. Relevant equations

    3. The attempt at a solution
    a) YES. The oscillating electrons produce a radio wave.
    b) YES. The AC current in the cord produces EM radiation.
    c) maybe. The electrons go round in the circuit but does that produce EM radiation?
    d) maybe. Same as c) except protons. Not sure.
    e) NO. As it is direct current there is no oscillating electrons and therefore no EM radiation.

    Are these right? Please help with c) and d) as well, I'm really not sure.
  2. jcsd
  3. Jun 20, 2012 #2


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    Staff: Mentor

    In (d), is the charged particle being accelerated in any manner?
    In (e), does the wire have zero ohms resistance? If not, then it will be shedding heat. Also, presumably there is a switch, and when current is switched on or off it produces a pulse of radiation.
  4. Jun 20, 2012 #3
    Thanks for the reply,
    In (d) the charged particle would be accelerating (would this produce X-rays, or is that only decelerating electrons?).
    as for (e) I suppose there would have to be a switch, what causes this pulse of radiation when it is switched?

    As for a, b, and c, would you say they are reasonable answers?
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