Physics-
General
Easy
Question
The graph. Shown in the adjacent diagram, represents the variation of temperature (T) of two bodies, x and y having same surface area, with time (t) due to the emission of radiation. Find the correct relation between the emissivity (e) and absorptivity (a) of the two bodies
The correct answer is:
Rate of cooling 
emissivity (e)
From graph, 
Þ 
Further emissivity (e) µ Absorptive power (a) Þ
(
good absorbers are good emitters).
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