Terms beginning with E

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A phenomenon whereby individuals report a number of symptoms which they claim are due to exposure to various man-made sources of electromagnetic radiation. According to current scientific knowledge, no causal relationship between exposure to electromagnetic radiation and the reported symptoms has been established.קרא עוד >

A phenomenon occurring in space where an electric charge exists and in which a difference in electric tension occurs.  In fact, any charged body creates an electric field around itself, that affects (exercises power over) any other charged body in its vicinity.  For example: If an object is charged by a static electric charger, it will attract hair, dust, floating particles, etc.  The electric field is measured in units of volts per meter (V/m).קרא עוד >

A combination of electric and magnetic fields spreading through space in waves with distinct physical characteristicsקרא עוד >

The energy of magnetic electrical activity spreading in waves in a vacuum or through matter.קרא עוד >

A continuous scale of frequencies (or wavelengths) describing different types of electromagnetic radiation.  It ranges from the lowest frequency (corresponding to the longest wavelength) and to the highest frequency (corresponding to the shortest wavelength).  The scale is divided into segments of different frequencies according to their actual usage, their physical features, and their possible health effects.קרא עוד >

Negatively-charged basic particle in the atom.קרא עוד >

A segment of the electromagnetic spectrum. ELF includes frequencies in the range 30-300 Hz (particularly high wavelengths, from 1000 to 10000 km, respectively).  Frequencies of the electric power grid are generally 50 or 60 Hz.  Examples of ELF electromagnetic fields: electric power lines, transformers, electric chargers, etc.)קרא עוד >

The ability of a system to perform work. Energy is one of the basic characteristics of any system.  Energy may be converted from one form to another, e.g., mechanical to electrical energy.קרא עוד >

Any exposure to electromagnetic radiation that is not occupational or medical.קרא עוד >

A derivative of the general exposure threshold, aimed at protecting the environment and humans in public areas against the harmful effects of a chemical or physical agent.In certain cases the purpose of this threshold is to minimize exposure before irreversible damage is caused.קרא עוד >

A branch of medicine that deals with the distribution of states of health and disease in the population, and with the detection of risk factors and causation of diseasesקרא עוד >

The addition of a discrete amount of energy (called excitation energy) to an atom or a molecule that results in its alteration, ordinarily from the condition of lowest energy (ground state) to one of higher energy (excited state). Excitation may result from absorption of a photon or from collision with energetic electrons. The life span of an excited electron is usually very short; when the electron returns to its ground state or to a state of lower energy, energy is released.   קרא עוד >

A threshold value protecting the public from irreversible harmful effects of a chemical or physical agent.קרא עוד >