Electromagnetism Spectrum. Electromagnetic radiation - Assignment Example

? Electromagnetism spectrum Electromagnetic radiation (EMR) is one of the key phenomena of electromagnetism, which behaves as photonparticles or propagating waves travelling through space loaded with radiant energy (Abdo 2007). These waves characteristically travels at a speed of light in vacuum and in a straight line (Abdo, 2007). As a wave, EMR can characteristically be absorbed or emitted by charged particles. They also have the magnetic field, as well as electric component that oscillates perpendicularly and in fixed relationship with each other and perpendicular to the direction of the wave energy propagation. Electromagnetic waves are characterized by wavelength and frequency of their waves. In order of decreasing wavelength and increasing frequency, electromagnetic spectrum consists if the radio waves, the microwaves, the infrared radiation (IR) the visible light (UV), the ultraviolet radiation, the X-rays and finally the Gamma rays. In this spectrum, higher frequency and lower wavelength corresponds to proportionately more energy possessed by each photon. For example in this case, gamma rays photon has more energy compared to a Visible light photon. The characteristics of electromagnetic waves are shown in diagram 1 and 2. Diagram 1: Properties of the EM spectrum across each range. Diagram 2: Electromagnetic spectrum. EMR is often associated with electromagnetic fields, which propagates themselves freely without the influence of moving charges responsible for producing them because they operate at a distance from the charges that produced them (Condon, & Ransom, 2003). This way, EMR is also referred to as far field. In this context, near field EMR refers to those electromagnetic fields near the current and charges, which directly produced them. The static electricity and magnets phenomena are the best examples of near field EM. In electromagnetic radiation, the electric and magnetic fields are often induced by the changes in electric fields. This makes it to propagate itself as a wave. Such as relationship ensures both the electric and magnetic types of the fields stand in a fixed ration of their intensity to each other and in phase with nodes and maxima found at similar places in space. Electromagnetic radiations carries energy called radiant energy through space and continuously away from its source. They also carries both angular momentum and momentum, all of which are impacted matter upon which EMR interact with. Electromagnetic waves are often produced from other forms of energy when they are created, and they are converted to other forms of energy whenever they get destroyed. The photon is the basic unit and constituent of all form of electromagnetic radiation, and is the quantum of the EMR interaction. In classical physics, electromagnetic radiation is considered produced whenever forces act on charged particles to accelerate them. Fast moving electrons are sharply accelerated whenever they meet any region of force. Electrons are therefore, responsible for the production of most high frequency EMRs such as X-rays. This is because of their associated low mass. Quantum process also produces EMR. This happens when an atomic nuclei is made to under a process such as neutral pion decay or gamma decay. The effects of electromagnetic radiations on biological systems depends on the radiation’s frequency and power. Health effects of Electromagnetic waves In the 21st century, exposure to manmade EMR fields has been increasing steadily with increasing growing energy demand. Changes in social behavior, as well as the ever-advancing technologies have created more artificial sources of EMR. We are exposed to mix of weak magnetic and electric fields both at work and at home from the domestic appliances, industrial equipment, generation and transmission of electrical energy, and in broadcasting and telecommunication. There exists tiny electrical currents within human bodies because of chemical reactions, which occur as part of bodily functions, even where external electric fields are not present. For example, nerves in human beings often relay information by transmitting electric impulses. In the human body, most of the biological reactions occurring right from digestions to the activities of the brain follow a certain pattern involving the arrangement of charged particles. Low-frequency electric fields often influence the body in the similar way they do in other materials, which are constituted by charged particles. Whenever electric fields act in a conductive material they do so by influencing the way electric charges are distributed on the surface of the conductive material. These currents often induce circulating currents in the body. The strength of these low-frequency currents entirely depend on intensity of the magnetic field outside these currents. Where these currents are sufficiently large, they can cause muscle and nervous stimulation. The currents may also affect other biological processes. The magnetic fields and electric fields often induce currents and voltages in the human body but even beneath a very high voltage transmission lines, the currents that induced are relatively very small when compared to the threshold for the production of shock and other related electric effects. The major biological effect of electromagnetic field of radiofrequency fields is heating. This fact is explored in microwave ovens to heat food. In most cases, levels of radiofrequency fields people are exposed to are often much lower than the amount required to cause a significant heating. The current guidelines are based on the radio waves heating effect. Studies have also sought to find out the possibility that some effects below the required level for body heating take place due to long-term exposure to the radio waves. However, so far, low level, or long-term exposure to power frequency or radiofrequency fields have not be linked to any adverse effects. It remains undisputed that electromagnetic fields much above a certain level may trigger biological effects. Experiments have indicated that short-term exposure to EMR present in the home or the environment do not have apparent detrimental effects. However, for safety purposes the national and international guidelines have restricted exposure to high energy EMR. Currently, the debate is on whether long-term low level exposure may induce biological responses. Biological effects can be the measurable responses to an environmental change or a stimulus. Such changes are not as such harmful to human health. For example reading a book, listening to music, playing tennis, eating an apple will produce various biological effects. However, none is expected has health effects. The human body has sophisticated mechanisms by which it adjusts to varied influences it encounters. Ongoing change is part of normal life. However, the human body lacks adequate compensation mechanism for some of the biological effects. It does, however, posse adequate mechanisms for major biological effects. Those changes, which are irreversible and tend to stress the body for an extended period of time constitute a health hazard. References Abdo .A., 2007. "Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy". The Astrophysical Journal Letters 658. Condon, L., & Ransom.M., 2003. "Essential Radio Astronomy: Pulsar Properties. New York: Oxford. Read More