There is much confusion in existing textbooks with regard to the terminology used in connection with emission and absorption of radiation. We shall use, in this chapter, the terminology of the international critica1 tables.
Total emissive power: As already stated, the quality and quantity of radiation emitted by a body depend on the temperature of the body. They also depend on the degree of polish of the radiating surface.
By total emissive power of a body, we shall mean the total energy associated with all the wavelengths in the radiation emitted per unit area of a surface of the body per unit time in all possible directions.
The total emissive power will be represented by Es and will be expressed ...