Wien's Law Calculator
Calculate peak wavelength and temperature using Wien's displacement law for blackbody radiation
Calculate Using Wien's Displacement Law
Absolute temperature of the blackbody
Wien's Law Results
Example: Solar Surface Temperature
Solar Observation
Peak wavelength: λ_max ≈ 501.7 nm (green-blue)
Observed spectrum: Maximum emission in visible light
Wien's displacement constant: b = 2.8977719 × 10⁻³ m·K
Temperature Calculation
T = b / λ_max
T = (2.8977719 × 10⁻³) / (501.7 × 10⁻⁹)
T = 2.8977719 × 10⁻³ / 5.017 × 10⁻⁷
Solar Surface Temperature ≈ 5,776 K (5,503°C)
Stellar Classification
Wien's Law Constants
EM Spectrum Regions
Understanding Wien's Displacement Law
What is Wien's Law?
Wien's displacement law describes the relationship between the temperature of a blackbody and the wavelength at which it emits the most radiation. It states that the peak wavelength is inversely proportional to temperature - hotter objects emit light at shorter wavelengths.
Key Applications
- •Stellar temperature determination from color
- •Thermal imaging and infrared astronomy
- •Incandescent lighting design
- •Climate science and Earth's energy balance
Mathematical Formulas
λ_max = b/T
f_max = k × T
- λ_max: Peak wavelength (meters)
- f_max: Peak frequency (Hz)
- T: Absolute temperature (Kelvin)
- b: Wien's displacement constant (2.898×10⁻³ m·K)
- k: Frequency constant (5.879×10¹⁰ Hz/K)
Important: Wien's law applies to ideal blackbodies, but provides good approximations for real objects like stars and heated materials.
Color and Temperature Relationship
Wien's law explains why hot objects glow in different colors. As temperature increases, the peak wavelength shifts to shorter wavelengths (blue shift), explaining why cooler stars appear red while hotter stars appear blue-white.
Red Hot
~800-1200 K
Peak: ~3000 nm
Yellow Hot
~5000-6000 K
Peak: ~500 nm
Blue Hot
~10000-30000 K
Peak: ~100-300 nm
UV Hot
> 30000 K
Peak: < 100 nm