what is radiation explain
Answers
Explanation:
Radiation is energy that comes from a source and travels through space and may be able to penetrate various materials. Light, radio, and microwaves are types of radiation that are called nonionizing. The kind of radiation discussed in this document is called ionizing radiation because it can produce charged particles (ions) in matter.
Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because unstable atoms have an excess of energy or mass or both. Radiation can also be produced by high-voltage devices (e.g., x-ray machines).
Atoms with unstable nuclei are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation. The kinds of radiation are electromagnetic (like light) and particulate (i.e., mass given off with the energy of motion). Gamma radiation and x rays are examples of electromagnetic radiation. Gamma radiation originates in the nucleus while x rays come from the electronic part of the atom. Beta and alpha radiation are examples of particulate radiation.
Interestingly, there is a "background" of natural radiation everywhere (ubiquitous) in our environment. Ubiquitous background radiation comes from space (i.e., cosmic rays) and from naturally occurring radioactive materials contained in the earth and in living things.
In this mode of the heat transfer there is no any requirement of the medium. Heat is flowing with the help of the electromagnetic wave . Heat radiation rate depends on the temp of the body. Surface finishing and wavelength of the wave emiting. Body are divided into the following on the basis of their heat radiation.
Those body which absorb the total light (heat) which is incident on the body is known as the black body.
Those body which absorb some heat also reflect some other heat are called non - Black body.