Mon January 24, 2011 By: Aditi Priya

A polished metallic piece and a black painted wooden piece are kept in open in bright sun for a long time : (a)the wooden piece will absorb less heat than the metallic piece., (b) the wooden piece will have a lower temperature than the metallic piece , (c) if touched the metallic piece will be felt hotter than the wooden piece ,(d) when the two pieces are removed frm the open to a cold room the wooden piece will lose heat at a faster rate than the metallic piece which of the following options are correct.

Expert Reply
Tue January 25, 2011
Dear student,
C and D
from metallic peice, more heat is conducted into the body than from a wooden peice. So, C is correct.
Wooden peice will act as a black body and it will absorb more heat as compared to a polished metallic peice when placed in open in bright sun. According to kirchoff's law, as a good absorberis also a good emitter, wooden peice will lose heat at a faster rate than the metallic peice.
Hope this helps.
Thanking you
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