In the context of the electromagnetic spectrum, what does frequency refer to?

Frequency is an important concept in understanding the electromagnetic spectrum, and it specifically refers to the number of complete waves that pass a given point in one second. This measure is typically expressed in Hertz (Hz), where one Hertz corresponds to one wave passing per second.

In the context of the electromagnetic spectrum, different types of electromagnetic radiation, such as radio waves, microwaves, and visible light, are characterized by their frequencies. Higher frequencies correspond to shorter wavelengths and higher energy, while lower frequencies correspond to longer wavelengths and lower energy.

Understanding frequency is essential when studying how different types of electromagnetic waves interact with matter and how they behave in various applications, such as communication and imaging technologies. This makes option B the correct choice as it accurately defines frequency within the context of the electromagnetic spectrum.