In the electromagnetic spectrum, which of the following is ordered from longest wavelength to shortest?

The electromagnetic spectrum is organized according to the wavelength of electromagnetic radiation, with the longest wavelengths at one end and the shortest at the other. Radio waves have the longest wavelengths, measuring from about one millimeter to kilometers. Following radio waves are microwaves, which have shorter wavelengths that range from about one millimeter to one meter. Next in the spectrum is ultraviolet radiation, with even shorter wavelengths ranging from about 10 nanometers to 400 nanometers. Finally, gamma-rays possess the shortest wavelengths, typically less than 0.01 nanometers.

Thus, the sequence of the electromagnetic spectrum from longest wavelength to shortest is accurately represented by the answer choice, which begins with radio waves and progresses through microwaves, ultraviolet, and concludes with gamma-rays. This understanding of the arrangement of electromagnetic waves is essential for recognizing their various applications and properties.