Physics

Waves


A wave is a movement caused by a disturbance, and it travels through a medium.

An example of a wave is taken when a rock is thrown into a calm water lake, where the impact will cause a disturbance in the water, causing circular waves to propagate across the surface of the water.

There are also waves that we cannot see with the naked eye, such as radio waves, television waves, ultraviolet waves, and microwaves.

In addition to these, there are some types of waves that we know well, but do not normally identify, such as light and sound.

But what they have in common is that they are all energies propagated through a medium, and this medium does not accompany propagation.

Wave Classification

According to their nature the waves are classified into:

  • Mechanical WavesThese are waves that need a material medium to propagate, ie their propagation involves the transport of kinetic and potential energy and depends on the elasticity of the medium. It is therefore not able to propagate in a vacuum. Some examples are those that happen in springs and strings, sounds and liquid surfaces.
  • Electromagnetic waves: they are waves generated by oscillating electric charges and their propagation does not depend on the medium in which they are, and can propagate in vacuum and in certain material media. Examples are radio waves, radar waves, x-rays and microwaves.

All electromagnetic waves have in common their speed of propagation in vacuum, close to 300000km / s, which is equivalent to 1080000000km / h.

Why do sea waves break?

Knowing that waves in general have the fundamental characteristic of propagating energy without movement in the middle, how can we explain the phenomenon of breaking ocean waves, causing water movement near the coast?

In deep water the waves of the sea do not carry matter, but as they approach the coast, there is a sharp decrease in the depth where they are, causing the breakage of these waves and causing a movement of the entire body of water and the formation of currents.

Once broken, the waves of the sea cease to behave like waves.

As for the propagation direction the waves are classified as:

  • One-dimensional: that propagate in only one direction, like the waves in strings and stretched springs;
  • Two-dimensional: they are those that spread over a surface, like water in a lake when throwing a stone;
  • Three-dimensional: They are able to propagate in all dimensions, such as light and sound.

Regarding the direction of vibration the waves can be classified as:

  • Cross sections: are those caused by vibrations perpendicular to wave propagation, such as on a string:

  • Longitudinal: they are waves caused by vibrations with the same direction of propagation as sound waves.