The Radiant heat energy is a notion which is rather more nicely explained by Stefan’s law. This law elucidates how the heat is radiated! It states that The amount of heat which is radiated (E) by a flawless black body for a second in a provided unit area is directly related to the fourth power of its absolute temperature (T).
The Radiant heat energy formula is articulated as,
E α T4
E = σ T4
Stefan’s constant (5.67 × 10−8 W/m2/K4) is σ
Radiant energy is E
Absolute temperature is T
Example 1: The surface temperature of the moon in the daytime is 123 Celsius. Compute the radiant heat energy for 1 meter square area.
Known: T (Temperature) = 1230 C = 123 + 273 K = 396 K
σ (Stefans Constant) = 5.67 × 10−8 W/m2/K4
Radiant energy, E = σ T4
E = (5.67 × 10−8) × (396)4
E = 1394.32.
Thus, the radiant heat energy is 1394.32.
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