Electromagnetic Radiation –

Electromagnetic radiation waves are a junction of magnetic field with electric field that propagates in vacuum carrying energy. Light is an example of electromagnetic radiation. This concept was first studied by James Clerk Maxwell and later affirmed by Heinrich Hertz. Maxwell was a Scottish physicist and mathematician who was known for giving final form to the theory of electromagnetism, a theory that unites magnetism, electricity and optics. From this theory arise Maxwell’s equations, so named in his honor and because he was the first to describe them, joining Ampère’s law, Gauss’s law and Faraday’s law of induction.

Electromagnetic radiation propagates in space. It has a magnetic field and an electric field that generate each other and propagate perpendicular to each other and in the direction of propagation of energy, thus transporting energy in the form of electromagnetic radiation. Electromagnetic radiation varies according to the frequency of the wave. The light visible to human eyes is electromagnetic radiation, just like x-rays, the only difference between these two forms of radiation is in the frequency range that the human eye can visualize, that is, x-rays have a frequency range that is out of reach of human vision. Microwave oven waves are also electromagnetic waves.

The magnetic and electric fields obey the principle of superposition. The magnetic field and electric field vectors intersect and create the phenomenon of reflection and refraction. Light is an electromagnetic wave and in a non-linear medium such as a crystal, for example, it can suffer interference and cause the Faraday effect, the wave can be divided into two parts with different speeds. In refraction, a wave passing from one medium to another, with different density, has its speed and direction changed. A source of radiation, such as the Sun, for example, can emit light within a variable spectrum. Sunlight, when decomposed in a prism, enables the visualization of spectrums of various colors, as in the rainbow. Note the engraving:

Don’t stop now… There’s more after the publicity 😉

Decomposition of sunlight on the prism.

By Marco Aurélio da Silva