Infrared radiation is a type of electromagnetic radiation that is:

Infrared radiation is a type of electromagnetic radiation that is:

• A. Invisible to the eyes
• B. Visible
• C. Ultraviolet
• D. Sound

Answer: (A)

Infrared radiation lies just beyond the red end of the visible spectrum, with wavelengths longer than what our eyes can detect. Because of these longer wavelengths, infrared is invisible to the eyes. We can feel it as heat, and many devices are built to sense infrared energy even though we can’t see it. This distinguishes it from ultraviolet, which has shorter wavelengths and higher energy, and from sound, which is a mechanical wave and not electromagnetic. Visible light is what we can see, so infrared isn’t visible.

Infrared radiation lies just beyond the red end of the visible spectrum, with wavelengths longer than what our eyes can detect. Because of these longer wavelengths, infrared is invisible to the eyes. We can feel it as heat, and many devices are built to sense infrared energy even though we can’t see it. This distinguishes it from ultraviolet, which has shorter wavelengths and higher energy, and from sound, which is a mechanical wave and not electromagnetic. Visible light is what we can see, so infrared isn’t visible.