Question

We consider the radiation emitted by the human body. Which of the following statements is true:

• A. The radiation emitted is in the infrared region
• B. The radiation is emitted only during the day
• C. The radiation is emitted during the summers and absorbed during the winters
• D. The radiation emitted lies in the ultraviolet region and hence is not visible

Answer 1

The Correct Option is A

The question pertains to the radiation emitted by the human body and its characteristics. To solve this question, we need to understand the nature of radiation emitted by all objects, including human bodies, due to their temperature.

Explanation:

• Black-body Radiation: All objects at a temperature above absolute zero emit thermal radiation. The type of radiation emitted depends on the temperature of the object.
• Infrared Radiation: The human body, with an average temperature of about 37°C (98.6°F), primarily emits radiation in the infrared region of the electromagnetic spectrum. This is because at the temperatures typically found in everyday environments, objects and living beings emit radiation in the infrared region.
• Comparison with Other Options:
  • The radiation is emitted only during the day: This is incorrect because the human body continuously emits radiation regardless of the time of day.
  • The radiation is emitted during the summers and absorbed during the winters: This statement is incorrect because the radiation emitted by the human body is not dependent on seasonal changes.
  • The radiation emitted lies in the ultraviolet region and hence is not visible: This is incorrect because human body radiation does not fall in the ultraviolet range; it is primarily infrared.

Conclusion: Based on the understanding of black-body radiation, the correct answer is: "The radiation emitted is in the infrared region."