What type of spectrum does a heated rock emit?

[aerogurl2]

hi guys, i am having trouble with a problem. it's as goes:
if you heat a rock until it glows, its spectrum will be:
(a) a thermal radiation spectrum
(b) an absoprtion line spectrum
(c) an emission line spectrum

I think it's thermal radiation spectrum because it seems like the rock is retaining heat thus making it glow. but I'm not sure. can someon please help me. thanks.

 

[berkeman]

You are correct. It will be giving off broad spectrum "black body" thermal radiation.

Quiz Question -- what physical mechanism results in absorption and emission "line" spectra?

 

[aerogurl2]

i don't really know. i just know thermal is heat and that's why the rock heats up.

 

[denverdoc]

Try here for a start: http://en.wikipedia.org/wiki/Black_body