Radiations; Solar Radiations.

Solar radiation is the set of electromagnetic radiation from the Sun. The Sun is a star that is at an average temperature of 2 K.

Sun energy released to the outside is transmtted through the solar radiation.

Solar radiation is distributed from the infrared to the ultraviolet. Not all of the radiation reaches the Earth's surface because the shorter ultraviolet waves are absorbed by the gases of the atmosphere primarily by ozone.

∙Solar radiation effects on atmospheric gases.

-Rotate a molecule.

-Make vibrate a molecule.

-Dissociate a molecule.

∙Excessive exposure to sunlight can be harmful to health. This is compounded by the increase in life expectancy, which is leading the world's population, to stay longer exposed to solar radiation, with increased risk of skin cancer.

¡ To avoid this it is advisable to take sunscreen of high level

NUCLEAR RADIATION

The nuclear radiation is very dangerous, we can see its effects little by little during a long time but, it doesn’t mean that its effects are less harmful.

Its effects damage the human’s health.

The principal source of this, are the nuclear centrals, when a nuclear central breaks, all their radioactive contaminants go out, the most influential contaminants for the human health are:

- Yodo: It affects immediately and it leaves mutuations in the genes.

- Estroncio: It accumulates in the bones, minimum 30 years.

Both increase the risk of all types of cancer.

This type of radiation also affects the environment. Little by little this contamination is deposed on the floor and in the sea, so it affects all living creatures of those places.

Measures to prevent the radiation:

·The nuclear centrals should be far away from you.

·When the nuclear radiation expands you have to be inside a flat and close all the windows and doors not to permit that the contaminant air enter.

. Also we can take yodo tablets to protect thyroid gland.

A black body emit radiation

A black body is an opaque object that emits thermal radiation. A perfect black body is one that absorbs all the light and doesn´t reflects anything. At room temperature, an object of this type should be perfectly black (so it is called black body.). However, if we heat it to a high temperature, a black body begins producing thermal radiation and shines.

All objects emit thermal radiation (as long as its temperature is above absolute zero, or -273.15 ºC), but there is not an object that actually is a perfect emitter because they emit or absorb better wavelengths of other lights more than others.

Electromagnetic radiation

Electromagnetic radiation refers to a form of energy emitted and absorbed by charged particles, which exhibits wave-like behaviour as it travels through space. It has both electric and magnetic field components, which stand in a fixed ratio of intensity to each other and which oscillate in phase, perpendicular to each other and perpendicular to the direction of energy and wave propagation.