The rate of heat loss by radiation is governed by the Stefan-Boltzmann Law, which states that the power radiated by an object is proportional to its emissivity, its surface area, and the fourth power of its absolute temperature. When considering heat exchange between an object and its surroundings, the net rate of heat loss is proportional to the difference in the fourth powers of their absolute temperatures. For practical purposes, especially when the temperature difference is not extremely large, the temperature difference itself is a direct indicator of the rate of heat loss.
A hot object loses heat to its surroundings in the form of heat radiation. The rate of loss of heat depends on the- - temperature of the object - temperature of the surroundings - temperature difference between the object and its surroundings - average temperature of the object and its surroundings
Asked in HORTICULTURE DEVELOPMENT OF‐ FICER(HDO) 2015 · Topic: Heat and Thermodynamics (Blackbody Radiation and Laws (Stefan-Boltzmann, Wien's Displacement))
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