Question

-Define in your own words "blackbody radiation" and explain how an old-fashioned filament light blub works and draw with labeled axes what its emission spectrum looks like. How is this concept important to understanding global climate change?

-How is the rainbow reflected off a dvd generated (i.e. what is the physical process by which colors are dispersed?)

Answer 1

First and foremost thing is An ideal Black body doesn't exist. A very near and good approximation is a hollow enclosure having blackened inner walls and a small hole any radiation is going into (entering) the enclosure through the hole suffer reflection repeatedly and get absorbed inside. If this enclosure is heated to a temperature T, it emits radiation. A very small fraction of the radiation will pass out through this hole. Since this hole acts as a Blackbody. This radiation is called Black body radiation .

The old-fashioned bulb uses a filament of high melting point. When the current is flowing through the filament due to its resistance and heating effect of current, it glows as Heat and light.  

Am Spectral distribution of Blackbody Radiation

The rainbow effect is due to constructive and destructive interference of light from different layers if the film.

this type rainbow effect can be easily seen in Soap bubbles , surfaces CDs and DVDs and oil floating on water.

..

...

#Hi, If you are happy and find this useful please thumbs up. In case, if you have any query regarding the solution please let me know in the comments section below. Thanks!!