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Question
A hot body is placed in a closed room maintained at a lower temperature. Is the number of photons in the room increasing?
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Solution
As the hot body is placed in a closed room maintained at a lower temperature, there will be transfer of heat in the room through convection and radiation. Heat radiation also consists of photons; therefore, photons will be emitted by the hot body. Hence, the number of photons in the room will increase.
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