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Ionospheric Radiation Absorption

  1. Dec 19, 2009 #1
    Hi All,

    I've read the reason for longer radio waves being absorbed by the ionosphere more than shorter waves and the argument goes like this:

    The longer waves cause the ions in the ionosphere to travel a longer distance during a typical RF cycle because the time subjected to the electric field on each half of the cycle is longer. This longer distance causes more ions to crash into each other and the crashing into each other is the reason for more energy being absorbed.

    It seems to me that the crashing of particles into each other has nothing to do with the additional absorption of energy. The ions, being subjected to a longer time in the electric field, attain a higher velocity and it is this increase in kinetic energy that the particles attain on each cycle which is responsible for the increased absorption and not the crashing of the particles into each other.

    As I see it, once a particle takes energy from a wave it doesn't matter what happens to the particle. The crashing only changes the direction of the particle and any energy the particle has is simply shared with its neighbors into which they are crashing.

    Is my logic correct?

    Thank you,

  2. jcsd
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