Use the formula $\lambda_{m} T = 0.29 \; cm \cdot K$ to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you?

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(N/A) body at a particular temperature produces a continuous spectrum of wavelengths. In the case of a black body,the wavelength corresponding to the maximum intensity of radiation is given by Wien's displacement law: $\lambda_{m} = \frac{0.29}{T} \; cm \cdot K$.
Where,$\lambda_{m}$ is the wavelength of maximum intensity and $T$ is the absolute temperature.
Using this relation,we can calculate the temperature for different wavelengths:
$1$. For $\lambda_{m} = 10^{-4} \; cm$ (Infrared region),$T = \frac{0.29}{10^{-4}} = 2900 \; K$.
$2$. For $\lambda_{m} = 5 \times 10^{-5} \; cm$ (Visible region),$T = \frac{0.29}{5 \times 10^{-5}} = 5800 \; K$.
$3$. For $\lambda_{m} = 10^{-6} \; cm$ (Ultraviolet region),$T = \frac{0.29}{10^{-6}} = 290000 \; K$.
The numbers obtained indicate that specific temperature ranges are required to emit radiation in different parts of the electromagnetic spectrum. As the wavelength of the radiation decreases,the corresponding temperature required to produce that radiation increases.

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