Black Body|Fery's Black Body|Kirchoff's Law|Emissivity

Perfectly Black Body

A black body emits

If between wavelength lambda and lambda + dlambda , e_(lambda) and a_(lambda) be the emissive and absorptive powers of a body and E_(lambda) be the emissive power of a perfectly black body, then according to Kirchoff's law, which is true

The black body have

For perfectly black body emissivity (e) is

Radiation||Perfectly black body||Absorptive power||Emissive power

In Ferry's black body, the area of black body is

Assertion : A normal body can radiate energy more than a perfectly black body. Reason : A perfectly black body is always black in colour.