Question

Define emissive power and coefficient of emission of a body

Answer 1

Answer:EMISSIVE POWER

Explanation:emissive power of a body at a given temperature is the quantity of radiant energy emitted by the body per unit time per unit surface area of the body at that temperature

COEFFICIENT OF EMISSION OF A BODY:

It is the ratio of the emmisive power of the body at a given temperature to the emmisive power of a perfectly black body at the same temperature

Coefficient of emission, ' e = E/E_b

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.