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,

α T4

or

E = σ T4

Where,
Stefan’s constant (5.67 × 10−8−8 W/m2/K4) is σ ,

absolute temperature is T.

Some of the solved numerical based on Radiant Energy is provided underneath:

Problem 1: The surface temperature of the moon in the daytime is 123 Celsius. Compute the radiant heat energy for 1meter square area.

Known: T (Temperature) = 123 C = 123 + 273 K = 396 K

σ (Stefans Constant) = 5.67 × 10−8−8 W/m22/K44

Radiant energy, E = σ T44

E = 5.67 × 10−8−8 W/m2/K4 × (396)4

E = 1394.32.

Thus, the radiant heat energy is 1394.32.

Problem 2: If the radiant energy of the body is 129.34, calculate its surface temperature.

Known:

$T^{4}\,&space;=\,&space;\frac{E}{\sigma&space;}$
$Temperature,\,&space;T\,&space;=\,&space;\sqrt{4}\,&space;\frac{129.34}{5.67\times&space;10^{-8}}$
$T\,&space;=\,&space;218.54\,&space;K.$