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Blue light and an opaque object

  1. Mar 17, 2008 #1
    I need help with a problem that was discussed here on PF also....

    Snazzy, (or anybody! =) ] I need your thoughts again please!!!

    When blue light strikes an opaque object whose resonant frequency is lower than the frequency of blue light, what happens?
    A- The amplitude of the vibrations of the electrons in the object become larger.
    B- The object becomes warm
    C- The blue light is absorbed without reemission
    D- The blue light is reflected by the electrons in the object
    E- The blue light is transmitted through the object

    ...This is a very tough one for me...

    ....'Security''s answer was B, The object becomes warm.

    PF Admin Warren ('chroot') said, ""Becomes warm" means the same thing as "vibrates more rapidly." So this is not correct. If the light does not meet the material's "resonant frequency" (this is a bad way to describe this, by the way) then it will pass right through."
    ----He said "it will pass right through."

    This guy on Yahoo! Answers said "Blue light should be reflected"
    Another said "You see the blue light on it"


    I am open to discuss this problem... if you don't want to give me your answer...
    But it's pretty late here in the East Coast... so... well anyway, HELP!!!! =)

    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Mar 17, 2008 #2
    If the blue light is higher in frequency than the resonance frequency, and since the object is opague (presumably a metal), then the blue light will be reflected by the plasma electrons.
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