Enter the absolute temperature (K) and Stefan’s Constant (5.67*10^-8 W/m^2/K^4) into the calculator to determine the Radiant Energy.

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## Radiant Energy Formula

The following equation is used to calculate the Radiant Energy.

RE = σ * T^4

- Where RE is the Radiant Energy (Joules)
- T is the absolute temperature (K)
- σ is the Stefan’s Constant (5.67*10^-8 W/m^2/K^4)

To calculate the radiant energy, multiply Stefan’s Constant by the absolute temperature raised to the power of 4.

## How to Calculate Radiant Energy?

The following example problems outline the steps and information needed to calculate Radiant Energy.

**Example Problem #1**

- First, determine the absolute temperature (K). In this example, the absolute temperature (K) is determined to be 5 .
- Next, determine the Stefan’s Constant (5.67*10^-8 W/m^2/K^4)
- Finally, calculate the Radiant Energy using the formula above:

RE = σ * T^4

Inserting the values from above and solving the equation yields:

RE = 5.67*10^-8 * 5^4** = .0000354 **(Joules)

**Example Problem #2**

Using the same method as above, first, we need to measure or determine the variables required by the equation. For this example problem, these are provided as follows:

absolute temperature (K) = 6

Stefan’s Constant (5.67*10^-8 W/m^2/K^4)

Enter these given values into the calculator or above yields: **RE = σ * T^4 = .0000734 **(Joules)