Question

define emissive power and absorptive power

Answer 1

Emissive power and absorptive power both are related to Energy

Explanation:

Emissive power:- The energy generated by thermal radiation emitted from the surface of medium in all direction ,per unit time at particular temperature define as Emissive power.

Absorptive power:- It defined as energy ratio absorbed by a surface in a particular time from the incident energy on it, i.e

Absorptive power = Amount of energy absorbed÷ Amount of energy incident.

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.