Question

The radiation emitted by human body is:

• A. X-ray
• B. Ultra-violet radiation
• C. Infrared radiation
• D. Visible range radiation

Hint:

Human body emits thermal radiation mainly in the infrared region. This is why thermal cameras detect humans using infrared radiation.

Answer 1

The Correct Option is C

Concept:
Every object having temperature above absolute zero emits thermal radiation. The type of radiation emitted depends on the temperature of the object.

Step 1: Understand human body temperature.
The average temperature of the human body is approximately: \[ 37^\circ C \] or about: \[ 310\ K \]

Step 2: Type of radiation emitted.
At this temperature, the human body emits radiation mainly in the infrared region of the electromagnetic spectrum.

Step 3: Eliminate other options.
Human body does not normally emit X-rays.
Human body does not normally emit ultraviolet radiation.
Visible radiation is emitted by very hot objects such as glowing metals or stars, not normally by the human body. Therefore, the radiation emitted by the human body is: \[ \text{Infrared radiation} \] \[ \therefore \text{Correct Answer is (C)} \]