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Question 3.4: A furnace has walls of temperature 1600°C. What is the wavel...

A furnace has walls of temperature 1600°C. What is the wavelength of maximum intensity emitted when a small door is opened?

Strategy We assume the furnace with a small door open is a blackbody so that we can determine \lambda_{\max } from Equation (3.14).

\lambda_{\max } T=2.898 \times 10^{-3} m \cdot K (3.14)

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We first convert the temperature to kelvin.

 

T=(1600+273) K =1873 K

 

Equation (3.14) gives

 

\lambda_{\max }(1873 K )=2.898 \times 10^{-3} m \cdot K

 

\lambda_{\max }=1.55 \times 10^{-6} m =1550 nm

 

The peak wavelength is in the infrared region.

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