Rankers Physics

Thermal Physics: Practice Problem & Solution

We consider the radiation emitted by the human, body. Which of the following statements is true: (2003)
The radiation emitted is in the infrared regions
The radiation is emitted only during the day.
The radiation is emitted during the summers and absorbed during the winters.
The radiation emitted lies in the ultraviolet region and hence is not visible

Solution Explained:

To solve this problem, we apply the core principles of Thermal Physics. Understanding the underlying formula is key to arriving at the correct answer below:

The temperature of the human body is about $310 \text{ K}$. According to Wien's law, the maximum emission wavelength is around $9.3 \mu\text{m}$, which falls in the infrared region.

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