Radiation Emitted By Small Body Calculator

Stefan-Boltzmann Law:

\[ E_{emit} = \varepsilon \cdot \sigma \cdot T^4 \]

Emitted Radiation:

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1. What is the Stefan-Boltzmann Law?

The Stefan-Boltzmann Law describes the power radiated from a black body in terms of its temperature. It states that the total energy radiated per unit surface area of a black body is directly proportional to the fourth power of the black body's thermodynamic temperature.

2. How Does the Calculator Work?

The calculator uses the Stefan-Boltzmann Law:

\[ E_{emit} = \varepsilon \cdot \sigma \cdot T^4 \]

Where:

\( E_{emit} \) — Emitted radiation (W/m²)
\( \varepsilon \) — Emissivity (0-1)
\( \sigma \) — Stefan-Boltzmann constant (5.670367 × 10⁻⁸ W/m²K⁴)
\( T \) — Absolute temperature (Kelvin)

Explanation: The law shows that radiation emitted increases dramatically with temperature due to the fourth power relationship.

3. Importance of Emitted Radiation Calculation

Details: Calculating emitted radiation is crucial for thermal analysis, heat transfer calculations, climate science, astronomy, and various engineering applications involving thermal radiation.

4. Using the Calculator

Tips: Enter emissivity value between 0 and 1, and temperature in Kelvin. Emissivity of 1 represents a perfect black body, while lower values represent real surfaces with less than perfect emission.

5. Frequently Asked Questions (FAQ)

Q1: What is emissivity?
A: Emissivity is the measure of an object's ability to emit infrared energy compared to a perfect black body. It ranges from 0 (perfect reflector) to 1 (perfect emitter).

Q2: Why is temperature in Kelvin?
A: The Stefan-Boltzmann law requires absolute temperature, and Kelvin is the absolute temperature scale where 0K represents absolute zero.

Q3: What are typical emissivity values?
A: Most surfaces have emissivity between 0.7-0.95. Polished metals can be as low as 0.02-0.2, while black surfaces approach 0.95-0.98.

Q4: Does this apply to all objects?
A: The law applies to ideal black bodies. For real objects, emissivity is introduced as a correction factor to account for deviations from ideal behavior.

Q5: How does temperature affect radiation?
A: Radiation increases with the fourth power of temperature. Doubling the temperature increases radiation by a factor of 16.