Question

Q.12 Define: Emmissive power and coefficient of emission.​

Answer 1

Answer:

EMISSIVE POWER - The energy of thermal radiation emitted in all directions per unit time from each unit area of a surface at any given temperature.

COEFFICIENT OF EMISSION - It is the ratio of the emissive power of perfectly black body at the same temperature.

HOPE THIS HELPS!!!

Answer 2

Answer:

(1) Emissive power or radiant power of a body (symn-

bol, R): The emissive power or radiant power of a

body at a given temperature is defined as the

quantity of radiant energy emitted by the body per

unit time per unit surlace area of the body at that

temperature.

(2) Coefficient of emission (or emissivity) of a body

(symbol, e): The coefficient of emission (or

emissivity) of a body is defined as the ratio of the

emissive power of the body (R) to the emissive

power of a perfect blackbody (R,) at the same

temperature as that of the body.