Wien's Displacement Law & Wiens Law constant

What is Wien's Law?

Wien's displacement law states that,

The temperature of a blackbody is inversely proportional to the wavelength at which it emits the most light.

The law is invented by Wilhelm Wien, a German physicist, who won the Noble prize for this invention.

The mathematical form of the rule is,

λmax= b/T

Where,

• T is the temperature in Kelvin
• λmax is the wavelength in meters
• b is Wien's displacement constant

Wien's constant

It is a physical constant which is equal to 2.898 x 10^-3 meter-kelvin. It defines the relation between wavelength and temperature of the black body when the emission of light is maximum.

Read: Types of Gas Welding Flames and its Application

That is why we can see the stars of different colors, the cool ones appear red, the hotter ones white and the hottest of all appear blue.

Wrap up

The law is very useful to find out information about stars or big objects. But Wien's law defines the energy distribution only in shorter wavelengths & fails to explain the energy distribution in a longer wavelength region.