Although waves come in many different shapes and sizes, there are many distinguishing characteristics that can be used to categorize them into different types of waves. The three main categories of waves include transverse, longitudinal, and surface waves. Waves can also be categorized into electromagnetic and mechanical waves.
One of the main characteristics of transverse waves is that the particles in the medium are traveling in a perpendicular direction to the direction in which the waves are moving. The easiest way to create transverse waves is by using a slinky. For example, if you were to introduce the energy of the slinky from the left side of the slinky to the right of the slinky, the particles of the medium (slinky) would travel in an up and down direction.
Unlike the particles of a transverse wave, in a longitudinal waves, the particles of the medium will travel in a direction parallel to the direction in which the waves are moving. Again, longitudinal waves can also be demonstrated by using a slinky. In this case, when energy is introduced from the left side of the slinky and then travels to the right side of the slinky, the particles of the medium (slinky) will also travel in a left to right direction. Sound waves moving through air (medium) is a common example of a longitudinal wave.
The particle movement of surface waves is very different compared to transverse and longitudinal waves. The particles of the medium of a surface wave travel in a circular motion. What’s interesting is that there is a larger amount of movement by the particles near the surface of the medium and as you increase the distance from the surface of the medium, there’s less particle movement.
As stated in the intro, waves can also be categorized into either electromagnetic or mechanical waves as well. The reason why these waves are categorized separate from the 3 types of waves above is because in these waves, we’re not focusing on particle movement; we’re focusing on whether or not the waves have the ability to transfer energy through a vacuum.
Electromagnetic Waves have the ability of transporting energy through a vacuum. For those who have not studied what a “vacuum” is, it’s not the thing you use to clean up your house; it’s actually an enclosed space that is completely neutralized of matter. Electromagnetic Waves play a major role in the support of life on Earth because the light that is transmitted between the sun and the Earth actually travel through waves that are electromagnetic. The reason for this is because space is an example of a vacuum and if the energy that was transmitted to the Earth from the Sun wasn’t electromagnetic, the energy would not have the ability to transfer. Light is a common example of a electromagnetic wave.
Unlike electromagnetic Waves, mechanical waves are not capably of transmitted energy through a vacuum. In order for mechanical waves to transmit energy, it has to travel through a medium. Sound waves are an example of mechanical waves. Sound is dependent on air in order to be transmitted meaning that without air (medium), you would not be able to hear anything.