Radio Waves and the Electromagnetic Spectrum

radio waves

There is some science that you can see in action. For example, chemical changes and reactions. But, what about what is not visible to the human eye? What about science such as cells and radio waves. In today’s blog, we’ll explore the science behind modern communication technology. Plus, give a rundown of the rest of the electromagnetic spectrum. 

What are Radio Waves?

Radio waves are a type of electromagnetic radiation with the longest wavelengths on the spectrum. In a vacuum, they travel at the speed of light. Meanwhile, in the Earth’s atmosphere, they move at a close, but slightly slower, speed. The sound that is heard is energy.

So, how does this happen? Well, radio waves are generated by charged particles undergoing acceleration, such as electric currents. Lightning and astronomical objects emit naturally occurring wavelengths. Additionally, they are part of the radiation released by all warm objects. We should note that they waves cannot be heard by the human ear or create acoustically.

Instead, transmitters artificially generate radio waves. Then, using antennas, radio receivers pick up the wavelengths. We can find this occurring in:

What’s more, different frequencies of radio waves (different wavelengths) have different spreading characteristics in the Earth’s atmosphere. For example, long waves bend around obstacles like mountains and follow the Earth’s ground waves. Meanwhile, shorter waves reflect off the Earth’s upper atmosphere and return to earth beyond the horizon in skywaves. Because of this difference, and that shorter wavelengths travel on a line of sight, these frequencies’ distances are limited to the visual horizon. 


James Clerk Maxwell first predicted radio waves by mathematical work in 1867. Now called Maxwell’s equation, he proposed that a couple electric and magnetic field could travel through space as an ‘electromagnetic waves”. What’s more, he offered that light consisted of these waves with a very short wavelength. 

In 1887, Heinrich Hertz demonstrated the reality of Maxwell’s prediction. He showed that radio waves exhibition the same wave properties of light such as:

Later, in 1894, Guglielmo developed the first practical radio transmitters and receivers. This communication began commercial use around 1900. 

The Electromagnetic Spectrum

Radio waves exist on something called the Electromagnetic Spectrum. This is the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies. Let’s have a look at it from those with the longest wavelengths to the shortest.

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About the Author

Lydia B.

Lydia B.

Lydia B. is a Marketing Coordinator and Music Club Coach for Gooroo, a tutoring membership that matches students to tutors perfect for them based on their unique learning needs. Gooroo offers Math, English, SAT, Coding, Spanish tutoring, and more.