Sunday, July 4, 2021, 01:34 AM
A large number of properties and effects on nature, animated and lifeless, have to do with light. The first to keep in mind is that light has a double nature: Golf – Corpuscle. Today we look at the Golf. Waves, of every nature (sound, water, light, etc.) have ridges and valleys, For example, waves that occur in a lake when we throw a stone. The distance between two consecutive backs is the wavelength. Waves can also be characterized by frequency, measured in Hertzios (HZ) and are related to the reverse wavelength.
A very special and important type of waves are electromagnetic. They can spread both in empty space and in material media (solids, liquids and gases). In a vacuum they do it at a finite speed of 300,000 km per second. Its existence was demonstrated by Maxwell in 1873, a theoretical work that can be considered one of the basic pillars of our civilization. Electromagnetic waves receive different names, depending on their frequency (wavelength). Radio and television waves, whose frequency of a few Hertzios goes to a billion houses. By increasing the frequency, the microwave follows: they are used by radar and uhf band and, for example, microwave ovens. They are followed by infrared: it is those who broadcast hot bodies, for example the night views that appear in the films, detect the thermal radiation broadcast by the human body. The visible light then contains: includes a very small distribution of frequency (wavelengths), from 4 1014 Hz to 8 1014 Hz. The ultraviolets follow: the sun is a powerful source of these waves (radiation) that, thanks to the ozone layer, reach us to the surface of the nature, these waves destroy life, so they are used as a disinfectant. The following waves are X series, gamma and cosmic rays. The described golf assembly is what the electromagnetic spectrum is called.
For most burgers, light is the visible part of the electromagnetic spectrum. It is visible because the human eye only perceives the light for that small rank of frequencies. What about colors? As such, colors do not exist in nature. They are due to a perception that is built in our brains of the light that our eyes capture. A color travels for each frequency. The human retina is sensitive to the three fundamental: red, green and blue. The brain is responsible for recosing them to get the whole range. Moreover, the color we see from an object is that of the light that reflects, it is not an intrinsic property of the object. The objects have no color, they look color. These combinations of the three colors, additive or subtractive are used on television screens, printers, etc.
