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Electromagnetic
Energy
- is energy stored in electromagnetic waves or radiation. Energy is released
when the waves are absorbed by a surface. Any object with a temperature
above absolute zero (-273 degrees Celsius) emits this type of energy.
The intensity of energy released is a function of the temperature of the
radiating surface. The higher the temperature, the greater the quantity
of energy released.
On Earth, there are fundamentally three ways in
which energy can be transferred from one place to another: conduction,
convection, and radiation. Conduction consists of energy transferred directly
from molecule to molecule, and represents the flow of energy along a temperature
gradient. Convection involves the transfer of energy by means of vertical
mass motions of the medium through which heat is transferred (horizontal
transfer is called advection). In gases and liquids, this exchange by
mass motions is commonly seen in rising bubbles known as convection currents.
Both conduction and convection depend on a material medium in order to
operate. This medium can be gaseous, liquid, or solid. Radiation is the
only means of energy transfer through space without the aid of a material
medium, and is the major source of energy on the Earth.
Laws of Thermodynamics
The laws of thermodynamics describe some of the
fundamental truths of thermodynamics observed by scientists. Three laws
have been formulated:
First Law of Thermodynamics
Energy can be transferred from one "system"
to another in many forms. However, it can not be created nor destroyed.
Thus, the total amount of energy available in the Universe is constant.
This law is also called the Law of Conservation of Energy. Einstein's
famous equation (written below) describes the relationship between energy
and matter deals with this law:
E =MC2
In the equation above, energy (E) is equal to matter (M) times the square
of a constant (C).
Second Law of Thermodynamics
Heat can never pass spontaneously from a colder
to a hotter body. As a result of this fact, natural processes that involve
energy transfer must have one direction, and all natural processes are
irreversible. This law also predicts that the entropy of an isolated system
always increases with time. Entropy is the measure of the disorder or
randomness of energy and matter in a system.
Third Law of Thermodynamics
If all the thermal motion of molecules (kinetic
energy) could be removed, a state called absolute zero would result. Absolute
zero results in a temperature of 0 degrees Kelvin or -273.15 degrees Celsius.
Absolute Zero = 0 degrees Kelvin = -273.15 degrees
Celsius
The Universe will attained absolute zero when all energy and matter is
randomly distributed across space.
Electromagnetic
Cascade Shower
Electrons can create photons by interacting with a medium. In a similar
way, photons can create electrons and their antiparticles , positrons,
by interacting with a medium. So, imagine a very high energy electron,
of the sort used at SLAC, impinging on some material. The electron can
set photons into motion and these photons can, in turn, set electrons
and positrons into motion, and this process can continue to repeat. One
high energy electron can set thousands of particles into motion. Albert
Einstein's famous relation governing the equivalence of matter and energy
(E = mc²) governs this process -- namely, matter (electrons and positrons)
can be created from pure energy and vice versa. The particle creation
process only stops when the energy runs out.
This may explain how orbs manifest into apparitions or ecto. In this case
it is not ions, but with high energy electrons. Replace the word "medium"
with orb and see if you can fit it together.
Attenuation
The process by which a compound is reduced in concentration over time,
through adsorption, degradation, dilution, and/or transformation. Radiologically,
it is the reduction of the intensity of radiation upon passage through
a medium. The attenuation is caused by absorption and scattering.
Coherence
A term that's applied to electromagnetic waves . When they "wiggle"
up and down together (in phase) they are said to be coherent. A laser
is a good example of coherent light. An ordinary light bulb produces incoherent
light much like the random waves produced when many raindrops hit a puddle.
Electromagnetic radiation is coherent when the photons are produced in
such a way that they are in phase with one another and incoherent when
the phases of the photons are random. Partial coherence is an intermediate
situation where there a significant fraction of the photons have related
phase, but not all of them.
Ion
Atomic particle, atom, or chemical radical bearing an electrical charge
, either negative or positive.
Ionization
The process by which a neutral atom or molecule acquires a positive or
negative charge .
Ionizing
Radiation
Radiation that has enough energy to eject electrons from electrically
neutral atoms, leaving behind charge atoms or ions. There are four basic
types of ionizing radiation: Alpha particles (helium nuclei), beta particles
(electrons), neutrons, and gamma rays (high frequency electromagnetic
waves, x-rays, are generally identical to gamma rays except for their
place of origin.) Neutrons are not themselves ionizing but their collisions
with nuclei lead to the ejection of other charged particles that do cause
ionization .
Lepton
A fundamental matter particle that does not participate in strong interactions.
The charge leptons are the electron (e), the muon ( ), the tau ( ) and
their antiparticles . Neutral leptons are called neutrinos.
Neutrino
A lepton with no electric charge . Neutrinos participate only in weak
(and gravitational) interactions and therefore are very difficult to detect.
There are three known types of neutrino, all of which have very low or
possibly even zero mass.
Photon
The carrier particle of the electromagnetic interaction . Depending on
its frequency (and therefore its energy) photons can have different names
such as visible light, X rays and gamma rays . We describe light in several
ways. When we talk about "photons" we generally think of uncharged
particles with out mass that carry energy (but be careful, there are other
particles like this!). Photons of light are known by other names too,
such as gamma rays and x-rays. Low energy forms are called ultraviolet
rays, infrared rays, even radio waves! A photon is one of the fundamental
particle in nature and it plays an important role involving electron interactions.
Photons are the most familiar particles in everyday existence. The light
we see, the radiant heat we feel, microwaves we cook with, are make use
of photons of different energies. An x-ray is simply a name given to the
most energetic of these particles.
Polarization
A polarized particle beam is a beam of particles whose spins are aligned
in a particular direction. The polarization of the beam is the fraction
of the particles with the desired alignment.
Residual
Interaction
Interaction between objects that do not carry a charge but that contain
constituents that do have a charge. Although some chemical substances
involve electrically charged ions, much of chemistry is due to residual
electromagnetic interactions between electrically neutral atoms. The residual
strong interaction between protons and neutrons, due to the strong charges
of their quark constituents, is responsible for the binding of the nucleus.
Basic EM theory
I. Introduction
Electromagnetic Radiation, energy waves produced
by the oscillation or acceleration of an electric charge. Electromagnetic
waves have both electric and magnetic components. Electromagnetic radiation
can be arranged in a spectrum that extends from waves of extremely high
frequency and short wavelength to extremely low frequency and long wavelength
(see Wave Motion). Visible light is only a small part of the electromagnetic
spectrum. In order of decreasing frequency, the electromagnetic spectrum
consists of gamma rays, hard and soft X rays, ultraviolet radiation, visible
light, infrared radiation, microwaves, and radio waves.
II. Properties
There are three phenomena through which energy
can be transmitted: electromagnetic radiation, conduction, and convection
(see Heat Transfer). Unlike conduction and convection, electromagnetic
waves need no material medium for transmission. Thus, light and radio
waves can travel through interplanetary and interstellar space from the
sun and stars to the earth. Regardless of the frequency, wavelength, or
method of propagation, electromagnetic waves travel at a speed of 3 ×
1010 cm (186,272 mi) per second in a vacuum. All the components of the
electromagnetic spectrum, regardless of frequency, also have in common
the typical properties of wave motion, including diffraction and interference.
The wavelengths range from millionths of a centimeter to many kilometers.
The wavelength and frequency of electromagnetic waves are important in
determining heating effect, visibility, penetration, and other characteristics
of the electromagnetic radiation.
III. Theory
British physicist James Clerk Maxwell laid out
the theory of electromagnetic waves in a series of papers published in
the 1860s. He analyzed mathematically the theory of electromagnetic fields
and predicted that visible light was an electromagnetic phenomenon.
Physicists had known since the early 19th century
that light is propagated as a transverse wave (a wave in which the vibrations
move in a direction perpendicular to the direction of the advancing wave
front). They assumed, however, that the wave required some material medium
for its transmission, so they postulated an extremely diffuse substance,
called ether, as the unobservable medium. Maxwell's theory made such an
assumption unnecessary, but the ether concept was not abandoned immediately,
because it fit in with the Newtonian concept of an absolute space-time
frame for the universe. A famous experiment conducted by the American
physicist Albert Abraham Michelson and the American chemist Edward Williams
Morley in the late 19th century served to dispel the ether concept and
was important in the development of the theory of relativity. This work
led to the realization that the speed of electromagnetic radiation in
a vacuum is an invariant.
IV. Quanta of Radiation
At the beginning of the 20th century, however,
physicists found that the wave theory did not account for all the properties
of radiation. In 1900 the German physicist Max Planck demonstrated that
the emission and absorption of radiation occur in finite units of energy,
known as quanta. In 1904, German-born American physicist Albert Einstein
was able to explain some puzzling experimental results on the external
photoelectric effect by postulating that electromagnetic radiation can
behave like a particle (see Quantum Theory).
Other phenomena, which occur in the interaction
between radiation and matter, can also be explained only by the quantum
theory. Thus, modern physicists were forced to recognize that electromagnetic
radiation can sometimes behave like a particle, and sometimes behave like
a wave. The parallel concept, that matter also exhibits the same duality
of having particle like and wave-like characteristics was developed in
1923 by the French physicist Louis Victor, Prince de Broglie.
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