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Standard Effective Temperature Calculator

Standard Effective Temperature Formula:

\[ T_{\text{eff}} = \left( \frac{L}{4 \pi \sigma R^2} \right)^{1/4} \]

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W/m²K⁴

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1. What is the Standard Effective Temperature Formula?

The Standard Effective Temperature formula calculates the effective temperature of a black body based on its luminosity, radius, and the Stefan-Boltzmann constant. It represents the temperature a black body would have to radiate the same amount of energy per unit area.

2. How Does the Calculator Work?

The calculator uses the Standard Effective Temperature formula:

\[ T_{\text{eff}} = \left( \frac{L}{4 \pi \sigma R^2} \right)^{1/4} \]

Where:

Explanation: The formula derives from the Stefan-Boltzmann law, relating the total energy radiated per unit surface area of a black body to the fourth power of its temperature.

3. Importance of Standard Effective Temperature Calculation

Details: This calculation is fundamental in astrophysics for determining the effective temperatures of stars and other celestial bodies, helping classify stars and understand their energy output.

4. Using the Calculator

Tips: Enter luminosity in watts, radius in meters, and the Stefan-Boltzmann constant (default value provided). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the Stefan-Boltzmann constant?
A: The Stefan-Boltzmann constant (σ) is a physical constant that appears in the Stefan-Boltzmann law, with a value of approximately 5.67 × 10⁻⁸ W/m²K⁴.

Q2: Can this formula be used for non-black bodies?
A: The formula is derived for ideal black bodies. For real objects, additional factors like emissivity must be considered.

Q3: What are typical values for stellar temperatures?
A: Stellar effective temperatures range from about 2,000K for cool red dwarfs to over 40,000K for hot blue stars.

Q4: How does radius affect the effective temperature?
A: For a given luminosity, a larger radius results in a lower effective temperature, as the energy is spread over a larger surface area.

Q5: What units should be used for accurate calculations?
A: Use consistent SI units: watts for luminosity, meters for radius, and the standard value for the Stefan-Boltzmann constant.

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