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To calculate the amount/quantity of waves emitted by a magnetron

  1. Apr 2, 2010 #1
    1. how may the quantity, or amount, of microwaves produced by a magnetron due to a given power input be calculated?
    2. what unit may be used to constitute a quantity, or amount, of electromagnetic waves?

    regarding microwave ovens

    it is desired to calculate the amount (key word amount) of microwaves that are produced per second during the operation of a microwave appliance.

    how may this be done?

    regarding "key word amount", it is not know in what units this "amount" or "quantity" of waves may be measured in.

    basically it is desired to know the quantity of microwaves produced by a magnetron due to a given power input.

    perhaps the quantity can be expressed in terms of energy, as energy would be dependent on the quantity.

    what constitutes "one" electromagnetic wave. one particle? one photon?
    so perhaps the quantity could be measured in terms of number of photons?
    what unit would be used to consitute the quantity of waves?

    thank you very much

  2. jcsd
  3. Apr 2, 2010 #2
    Photoelectric effect , E=hf Energy of a photon
    h= plancks constant f is the frequency of the light.
    We could shoot the microwaves at a material the we know the work function of.
    the stopping voltage would be V=hf/e - w/e
    where w is the work function the minimum amount of energy of the photons to get electrons to flow in the material , e is the charge of an electron , this comes from K=eV
    the kinetic energy of an electron is charge times voltage , so you could hook up a function generator to the material and increase the voltage till electrons stop flowing and this would be your stopping voltage.
  4. Apr 2, 2010 #3


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    I am not aware of any formal definition for this. Whoever is asking the question would need to clarify what they really mean.
  5. Apr 2, 2010 #4
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