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Question
Earth’s mean temperature can be assumed to be 280 K. How will the curve of blackbody radiation look like for this temperature? Find out λmax. In which part of the electromagnetic spectrum, does this value lie? (Take Wien's constant b = 2.897 × 10−3 m K)
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Solution
Data: T = 280 K, Wien's constant b = 2.897 × 10−3 m K
λmax T = b
∴ `lambda_"max" = "b"/"T"`
= `(2.897 xx 10^-3 "m.K")/(280 "K")`
= 1.035 × 10−5 m
This value lies in the infrared region of the electromagnetic spectrum.
The nature of the curve of blackbody radiation will be the same, but the maximum will occur at 1.035 × 10-5 m.
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