What Two Characteristics Can Be Used to Classify Electromagnetic Rays?

Home Science Physics Matter & Free energy

electromagnetic radiations

physics

Alternating titles: electromagnetic wave

---

electromagnetic radiation, in classical physics, the flow of energy at the universal speed of light through free space or through a material medium in the form of the electrical and magnetic fields that make up electromagnetic waves such as radio waves, visible light, and gamma rays. In such a wave, time-varying electric and magnetic fields are mutually linked with each other at right angles and perpendicular to the direction of movement. An electromagnetic wave is characterized by its intensity and the frequency ν of the time variation of the electric and magnetic fields.

In terms of the modern quantum theory, electromagnetic radiation is the catamenia of photons (also called calorie-free quanta) through space. Photons are packets of energy hν that ever motility with the universal speed of lite. The symbol h is Planck's abiding, while the value of ν is the same as that of the frequency of the electromagnetic wave of classical theory. Photons having the same energy hν are all akin, and their number density corresponds to the intensity of the radiation. Electromagnetic radiation exhibits a multitude of phenomena as it interacts with charged particles in atoms, molecules, and larger objects of affair. These phenomena likewise equally the ways in which electromagnetic radiations is created and observed, the fashion in which such radiation occurs in nature, and its technological uses depend on its frequency ν. The spectrum of frequencies of electromagnetic radiation extends from very low values over the range of radio waves, television waves, and microwaves to visible low-cal and beyond to the essentially college values of ultraviolet low-cal, X-rays, and gamma rays.

Britannica Quiz

Physics and Natural Police force

What strength slows move? For every activity there is an equal and opposite what? There's zero Eastward = mc square nigh taking this physics quiz.

The basic properties and behaviour of electromagnetic radiation are discussed in this article, equally are its diverse forms, including their sources, distinguishing characteristics, and practical applications. The article besides traces the development of both the classical and quantum theories of radiation.

General considerations

Occurrence and importance

Close to 0.01 pct of the mass/energy of the entire universe occurs in the form of electromagnetic radiation. All human life is immersed in it, and modern communications technology and medical services are particularly dependent on one or another of its forms. In fact, all living things on World depend on the electromagnetic radiation received from the Sunday and on the transformation of solar energy by photosynthesis into establish life or by biosynthesis into zooplankton, the basic step in the food chain in oceans. The eyes of many animals, including those of humans, are adapted to be sensitive to and hence to meet the most abundant office of the Sun'southward electromagnetic radiation—namely, light, which comprises the visible portion of its wide range of frequencies. Green plants besides have high sensitivity to the maximum intensity of solar electromagnetic radiation, which is captivated by a substance chosen chlorophyll that is essential for found growth via photosynthesis.

Practically all the fuels that mod society uses—gas, oil, and coal—are stored forms of energy received from the Sun as electromagnetic radiation millions of years agone. Just the free energy from nuclear reactors does not originate from the Dominicus.

Everyday life is pervaded by artificially made electromagnetic radiation: food is heated in microwave ovens, airplanes are guided past radar waves, television sets receive electromagnetic waves transmitted by broadcasting stations, and infrared waves from heaters provide warmth. Infrared waves also are given off and received by automatic cocky-focusing cameras that electronically measure and set the correct distance to the object to be photographed. As presently as the Sunday sets, incandescent or fluorescent lights are turned on to provide artificial illumination, and cities glow brightly with the colourful fluorescent and neon lamps of advertisement signs. Familiar also is ultraviolet radiation, which the eyes cannot encounter only whose effect is felt as pain from sunburn. Ultraviolet low-cal represents a kind of electromagnetic radiation that can be harmful to life. Such is likewise true of X-rays, which are important in medicine as they let physicians to notice the inner parts of the body simply exposure to which should be kept to a minimum. Less familiar are gamma rays, which come up from nuclear reactions and radioactive decay and are part of the harmful high-energy radiation of radioactive materials and nuclear weapons.

stricklandmostaks98.blogspot.com

Source: https://www.britannica.com/science/electromagnetic-radiation

Share this post