Which electromagnetic waves have the longest wavelengths and lowest frequencies?

Radio waves possess the longest wavelengths and the lowest frequencies of all electromagnetic waves. The electromagnetic spectrum is organized by wavelength, and radio waves are situated at the opposite end of the spectrum compared to waves like infrared, ultraviolet, and X-rays.

Radio waves have wavelengths that can range from a few centimeters to several kilometers, allowing them to effectively transmit various types of information, including radio and television signals. Their low frequency, which can be as low as 3 kHz (kilohertz), contributes to their ability to travel long distances and penetrate through various materials, including buildings.

In contrast, other types of waves such as infrared waves, ultraviolet waves, and X-rays have shorter wavelengths and higher frequencies. Infrared waves have wavelengths shorter than radio waves but longer than visible light; ultraviolet waves have even shorter wavelengths and higher frequencies than visible light; while X-rays have some of the shortest wavelengths and highest frequencies in the electromagnetic spectrum, making them suitable for medical imaging but unsuitable for long-distance communication like radio waves. This understanding of the placement of these waves within the electromagnetic spectrum highlights why radio waves are distinguished by their long wavelengths and low frequencies.