Quick check from College Physics, 14.7 Radiation

Radiation: quick check

What is the change in the rate of the radiated heat by a body at the temperature $T_{1} = 20º C$ compared to when the body is at the temperature $T_{2} = 40º C$ ?

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Answer
The radiated heat is proportional to the fourth power of the absolute temperature. Because $T_{1} = 293 K$ and $T_{2} = 313 K$ , the rate of heat transfer increases by about 30 percent of the original rate.

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