Planck Distribution
- At given wavelength, the emissive power increases with increasing temperature
- As the temperature increases,more emissive energy appear at shorter wavelengths
- For low temperature ( K), all radiant energy falls in the infrared region and is not visible to the human eyes. That is why only very high temperature objects, such as molten iron, can glow.
- Sun can be approximated as a blackbody at 5800 K