Blackbody Radiation Calculator

Calculate the radiation emitted by a blackbody at a given temperature.

Instructions:

Enter the **temperature** of the blackbody in Kelvin (K).
Click “Calculate Radiation” to get the power emitted per unit area.

Blackbody radiation is a fundamental concept in physics that describes how objects emit radiation based on their temperature. This guide will help you understand blackbody radiation, how to calculate it, and provide practical examples, FAQs, and tables for better understanding.

What is Blackbody Radiation?

Blackbody radiation is the thermal electromagnetic radiation emitted by a perfect blackbody, an idealized object that absorbs all incident radiation and re-emits it based on its temperature. The radiation emitted depends solely on the temperature of the blackbody and follows Planck’s law.

Blackbody Radiation Calculation

To calculate blackbody radiation, you need to understand two key equations:

Planck’s Law: Describes the spectral density of electromagnetic radiation emitted by a blackbody.
Stefan-Boltzmann Law: Calculates the total radiated energy per unit surface area of a blackbody.

Stefan-Boltzmann Law

The formula for the Stefan-Boltzmann Law is:

E = σ * T^4

Where:

E: Radiated energy per unit surface area (W/m²)
σ (sigma): Stefan-Boltzmann constant (approximately 5.67 × 10⁻⁸ W/m²K⁴)
T: Absolute temperature in Kelvin (K)

Practical Example

Let’s calculate the radiated energy for a blackbody at a temperature of 3000 Kelvin.

Using the Stefan-Boltzmann Law:

E = 5.67 × 10⁻⁸ * (3000)^4

E = 5.67 × 10⁻⁸ * 81,000,000,000

E = 4,592.7 W/m²

So, the radiated energy of the blackbody at 3000 K is 4,592.7 W/m².

FAQs about Blackbody Radiation

Q: What is the significance of blackbody radiation? A: Blackbody radiation is important for understanding how objects emit and absorb radiation, which has applications in fields like astronomy, climate science, and thermodynamics.

Q: What is Planck’s Law? A: Planck’s Law describes the spectral density of radiation emitted by a blackbody in thermal equilibrium at a given temperature, showing how radiation intensity varies with wavelength.

Q: Why is the Stefan-Boltzmann Law important? A: The Stefan-Boltzmann Law provides a simple relationship between temperature and radiated energy, making it useful for calculating the total energy output of stars and other celestial bodies.

Blackbody Radiation Calculator Table

Parameter	Value	Unit
Temperature (T)	3000	Kelvin (K)
Stefan-Boltzmann Constant (σ)	5.67 × 10⁻⁸	W/m²K⁴
Radiated Energy (E)	4,592.7	W/m²