Transmission Of Heat Question 251
Question: Two identical objects A and B are at temperatures TA and TB respectively. Both objects are placed in a room with perfectly absorbing walls maintained at temperatures T $ (T _{A}>T>T _{B}). $ The objects A and B attain temperature T eventually which one of the following is correct statement
[CPMT 1997]
Options:
A) ?A? only emits radiations while B only absorbs them until both attain temperature
B) A loses more radiations than it absorbs while B absorbs more radiations that it emits until temperature T is attained
C) Both A and B only absorb radiations until they attain temperature T
D) Both A and B only emit radiations until they attain temperature T
Show Answer
Answer:
Correct Answer: B
Solution:
According to Prevost theory every body radiate heat at all temperature (except 0K) and also absorbs heat from surroundings. Q $ T _{A}>T $
Therefore Object A emits radiations more than the radiations it absorbs. and $ T _{B}<T $
Therefore Object B absorbs more radiations than it emits. After a certain time all bodies attains a common temperature.
BETA
