At what characteristic wavelength does a blackbody at room temperature radiate?

9.73154 × 10⁻⁶ m, infrared region

Explanation:

Using Wien's displacement law which states that the temperature and the wavelength of the blackbody radiation are inversely proportional.

So,

λmax= b/T

Where,  

λmax is the peak of wavelength

b is the Wien's displacement constant having value as

T is the Absolute Temperature in Kelvins . Room temperature = 298 K

So,  

λmax= b/T  = = 9.73154 × 10⁻⁶ m

This wavelength corresponds to infrared region.

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