How is E-M radiation produced?

(1) Accelerate charged particles back and forth like they do at the radio station.

(2) All objects with temperature above ``absolute zero'' emit E-M radiations

Wien's Law

The way the peak of the Planck curve changes with temperature is quantifies by Wien's Law .

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This is Powerful!

Q. What about radiation from humans?

Note that the radiation we are all using to see one another is reflected from the lights in the room (don't believe me? turn off the lights and see what you see).

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This is bad news for soldiers and out-of-bounds campers in Yosemite.

Q. What temperature needs to be reached for the Planck radiation of a solid to peak in the x-ray region ( tex2html_wrap_inline431 cm)?

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Note, solids don't ordinarily get this hot!



Michael Bolte
Wed Jan 14 23:06:17 PST 1998