How to Calculate Stefan Boltzmann
What is Stefan Boltzmann?
The Stefan-Boltzmann law quantifies thermal radiation emitted by objects. It states that radiated power is proportional to the fourth power of absolute temperature.
Formula
The calculator applies P = σ × ε × A × T⁴
- P
- σ × ε × A × T⁴ — σ × ε × A × T⁴
- A
- A value — Variable used in the calculation
Step-by-Step Guide
- 1Enter the object's surface area, emissivity, and temperature
- 2The calculator applies P = σ × ε × A × T⁴
- 3Results show total radiated power in watts
Worked Examples
Input
A = 1 m², T = 5778 K (Sun), ε = 1
Result
P ≈ 63 MW
Intense thermal radiation
Common Mistakes to Avoid
- ✕Using Celsius instead of Kelvin for temperature
- ✕Forgetting to apply the fourth power to temperature
Frequently Asked Questions
Why is the T⁴ dependence important?
Small temperature increases dramatically increase radiation; doubling absolute temperature increases power by 16×.
What is emissivity?
Emissivity (0-1) indicates how efficiently an object radiates; 1 is a perfect blackbody, less than 1 reflects some heat.
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