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Before we can learn about we need to know a little bit about
light (since that is what a laser is made of). Light from our sun, or from an
electric bulb, is called white light. It is really a mixture of all the
different colours of light. The colours range from violet, indigo, and blue, to
green, yellow, orange, and red. These make up the visible part of the
electromagnetic spectrum. Light is made up of particles, called PHOTONS, which
travel in waves. The difference in the colour depends on the wavelength of the
light. Violet light has the shortest wavelength while red has the longest. There
are other parts of the electromagnetic spectrum which includes infra-red, radar,
television radio and micro- waves (past red on the spectrum), and on the other
end of the spectrum are the other invisible radiations, ultra- violet, X rays,
micro waves and gamma rays. The wavelength of the light is important to the
subject of the laser. A laser is made up of COHERENT light, a special kind of
light in which the wavelengths of the light are all the same length, and the
crests of these waves are all lined up, or in PHASE. The word Laser is an
acronym for Light Amplification by Stimulated Emission of Radiation. What does
that mean? Basically a laser is a device which produces and then amplifies light
waves and concentrates them into an intense penetrating beam.
The principles of the laser (and it's cousin the maser) were established
long before these devices were successfully developed. In 1916 Albert Einstein
proposed stimulated emission, and other fundamental ideas were discussed by V.A.
Fabrikant in 1940. These ideas, followed by decades of intensive development of
microwave technology set the stage for the first maser (a laser made up of
micro-waves), and this in turn helped to produce more advances in this area of
science. These efforts cumulated in July 1960 when Theodore H. Maiman announced
the generation of a pulse of coherent red light by means of a ruby crystal-- the
first laser.
Laser light is produced by pumping some form of energy, such as light, from
a flash tube (see below) into a LASING material, also known as a medium. Media
can be liquids, solids, gases, or a mixture of gases, such as the common helium-
neon laser (see chart). Each medium produces a laser with a different wavelength
and therefore each medium produces different coloured light. When the energy, in
this case photons (light particles) enter the medium they smash into the atoms
of the medium. The atom then releases another photon of a ...
Down Syndrome is a chromosomal disorder. It occurs in about 1 of every 800 births. People with Down syndrome may have mild to severe learning disabilities. Physical symptoms include a small skull, extra folds of skin under the eyes, and a protruding tongue. People with Down syndrome are subject to a variety of medical problems including heart abnor...
In the late 1800's it was discovered that papa-amino-phenol, could reduce fever, but the drug was too toxic to use. A less toxic extract called phenacetin was later found to be just as effective but also had pain-relieving properties. In 1949, it was learned that phenacetin was metabolized into an active but also less toxic drug, . Since then, ha...
Mars is the fourth furthest away from the sun and is recognized by its reddish color. Mars is also very much like the Earth. " More than any other planet in the solar system, Mars has characteristics that make it an Earth-like world "(Grolier, 1992). One thing that is very similar to Earth is the rotation period. Mars rotation period is only thirty...
A new phase of matter has been discovered seventy years after Albert Einstein predicted it's existence. In this new state of matter, atoms do not move around like they would in an ordinary gas condensate. The atoms move in lock step with one another and have identical quantum properties. This will make it easier for physicists to research the my...
Hard Boiled eggs Place dozen eggs in large pot and fill with enough water to cover eggs. Bring eggs to boil, remove from heat, cover, and let sit for 20 minutes. Gently and carefully remove eggs from hot water, and place in bowl. Run cold tap water over eggs to cool off. ________________________________________ Non-boiled egg prep Gently ta...
A parent cell divides to make two smaller daughter cells that then grow into full size cells and may or may not divide like their parent. A nucleotide is made up of a phosphate a pentose or five carbon sugar and a one ring purimidie or a two ring purine In a the DNA double helix a purine always bond with perimedines this is known as complimentary...
Problem: The researcher is trying to determine whether or not cleaning materials will clean as well if they have been frozen solid and subsequently thawed out until they have returned to a liquid state of matter. The researcher will use Dial Antibacterial Kitchen Cleaner, Clorox Bleach, and Parson's Ammonia, applied to simple bacon grease, to dete...
Thesis: Large corporations, such as insurance companies, and governments are looking to save money on future policyholders through the use of genetic testing. General information on the Time of discussion leading up to implementation Who was involved Where does the funding come from Insurance Companies and discrimination Discrimination against u...
Genetic engineering, altering the inherited characteristics of an organism in a predetermined way, by introducing into it a piece of the genetic material of another organism. Genetic engineering offers the hope of cures for many inherited diseases, once the problem of low efficiencies of effective transfer of genetic material is overcome. Another...
"The roof was caving in and I thought I was going to die. It was like your worst nightmare!" said Mary Grandish. Most people think they will die when they see,or hear of a tornado heading their way. Although all the details of the formation of a tornado are not yet understood, it is known that tornados are the result of great instability in the...
is a combination of birth defects including some degree of mental retardation and characteristic facial features. It is also called trisomy 21. occurs when there is an abnormality in chromosome 21. It is found in approximately 1 out of 1000 all live births. Each year, 3,000 to 5,000 people are diagnosed with in the United States. T...
Homework #3b - II: Show your work under each question 1) You are riding your bike on a track that forms a vertical circular loop. If the diameter of the loop is 10.0 m, what is the minimum speed required for you to make it around the loop? 2) You are swinging a bucket of water in a vertical circle. Assuming that the radius of the rotation of...
Why do some parasites kill the host they depend upon while others coexist with their host? Two prime factors determine parasitic virulence: the manner in which the parasite is transmitted, and the evolutionary history of the parasite and its host. Parasites which have colonized a new host species tend to be more virulent than parasites which h...
This paper will define and discuss the volcano to include: types of volcanoes, formation of a volcano, and elements of a volcano; such as, lava, rock fragments, and gas. This paper also tells a little bit about volcanic activity in different parts of the world. What is a volcano? A volcano is a vent in the earth from which molten rock and gas er...
