Blue light and an opaque object

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When blue light hits an opaque object with a resonant frequency lower than that of blue light, the light cannot be absorbed or transmitted. Instead, it is reflected by the electrons in the object. The discussion highlights confusion around the concepts of absorption, reflection, and the relationship between light frequency and material properties. The consensus leans towards the idea that the blue light will be reflected rather than absorbed or transmitted. Overall, the interaction depends on the material's properties and the frequency of the incoming light.
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I need help with a problem that was discussed here on PF also...

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

QUESTION:
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"


ARGH! I'M SO CONFUSED!



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! =)



 
Physics news on Phys.org
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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