Classification of Waves
Sound Waves
Ocean waves and the waves on the Philippine flag are waves that you can see. However, there are other waves that are not visible to the human eye. These include sound waves, or disturbances in the air that carry sound from one point to another.
Air is made up of molecules and sound is able to travel through these molecules. Sound waves can travel through anything that has molecules, even in water!
Electromagnetic Waves
In contrast to sound waves, an electromagnetic wave is a type of wave that does not need molecules, or any other medium, to move from one location to another. It can travel through air, solid material, and even empty space.
An example of an electromagnetic wave that is most likely familiar to you are radio waves, or those waves that enable radios to function. Other examples are microwaves, infrared rays, visible light, ultraviolet rays, and gamma rays. All these electromagnetic waves travel at the speed of light that is 300 000 000 m/s. They differ in their frequencies, hence, in their wavelengths too. Radio waves have the least frequency, hence carry the least energy. Gamma rays, on the other hand, have the greatest frequency, thus, carry the greatest energy.
