In what unit is wavelength expressed?

Wavelength is a fundamental property of electromagnetic waves, including visible light, and is commonly expressed in various units depending on the scale of the wavelength being measured. Nanometers (nm) are a widely used unit for measuring wavelengths in the range of visible light and ultraviolet radiation, where wavelengths typically range from about 400 nm to 700 nm. This precision makes nanometers particularly useful in fields such as optics and laser technology, where understanding the specific wavelengths of light is crucial for applications like color perception, spectroscopy, and laser operation.

Other units also represent wavelengths, but they are used in different contexts. For example, centimeters might be more appropriate for longer wavelengths, such as those of radio waves, while picometers are often used for much shorter wavelengths found in X-rays and gamma rays. Micrometers can be suitable for infrared radiation but are less common for visible light wavelengths. Each of these units serves its purpose depending on the wavelength range being discussed, but for the visible spectrum, nanometers are the standard choice.