Smart Tan Certification Practice Exam

The wavelength range of visible light is accurately defined as spanning from approximately 400 nanometers (nm) to 700 nanometers. This range includes the colors that the human eye can perceive, from violet at the shorter wavelengths, to red at the longer wavelengths. The definition of visible light is critical in various applications, including understanding solar radiation, which impacts tanning and skin exposure.

Wavelengths shorter than 400 nm fall into the ultraviolet (UV) spectrum, which is not visible to the human eye, while wavelengths longer than 700 nm are classified as infrared. Therefore, the option that correctly identifies the range of visible light is the range of 400 nm to 700 nm, highlighting its significance in both photobiological processes and practical applications in tanning and skin health.