In SI units, the value of the Stefan-Boltzmann constant is_________________?
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Answer: A. 5.6697 × 10-8W/m2.°K4
Explanation
The universal Stefan-Boltzmann constant is established as approximately 5.6697 times 10^-8 W/m2·K4. This SI unit representation matches the required fourth power absolute temperature formulation. Standard engineering reference data confirms this exact numerical value for thermal calculations. Universal physical constants are determined through precise international metrology measurements. Stefan-Boltzmann constant links black body radiation flux directly to absolute temperature values. Units combine power, surface area, and absolute temperature to the fourth power.
Radiation heat transfer computations in industrial furnaces rely on this exact constant value. Boiler design standards mandate using this standard SI constant for radiant section evaluations. Thermodynamic textbooks and engineering handbooks universally list this precise numerical constant. Option B uses an English engineering unit scaling factor instead of the correct SI value. Option C uses obsolete calorie thermal units instead of standard SI Watt power units. Option D combines English unit scaling factors with calorie energy units incorrectly.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
- Difficulty
- medium
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