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Galileo's Astronomical Observations, 2004.
An analysis of the significance of Galileo's early astronomical observations on the Aristotelian theory of the universe.
2,145 words (approx. 8.6 pages), 12 sources, MLA, $ 67.95
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Abstract
This paper looks at how, as Galileo first turned his telescope toward the heavens, he was drastically turning mankind away from its long-accepted view that the Aristotelian view of the heavens was correct. It examines the significance of Galileo?s early astronomical observations on the Aristotelian universe by examining Aristotle?s theory of the cosmos, pertinent background on Galileo, his discoveries, and the effect they had on Aristotle?s universe.
Outline
Introduction
Aristotle?s Universe
Galileo Leading Up to His Discoveries
Galileo?s Observations and their Significance
The Moon
Jupiter
Venus
Other Important Observations
Toward a Heliocentric Model
Conclusion
From the Paper
"The next object Galileo turned his attention to was the planet Jupiter. In January of 1610, he saw three small but bright stars in the area of Jupiter that changed positions with time, but never strayed far from Jupiter. After repeated observations, Galileo concluded that there are three stars in the heavens moving about Jupiter. He later discovered a fourth satellite of Jupiter and he named these moons the Medicean stars. These satellites were seen to orbit Jupiter at various distances and speeds. This was the first time that a planet other than Earth was found to have satellites orbiting it."
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Contemporary Theoretical Physics, 2004.
An overview of several contemporary theories in physics.
2,550 words (approx. 10.2 pages), 6 sources, MLA, $ 77.95
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Abstract
This paper introduces and explains several theories in physics, such as the M theory, string theory, quantum mechanics, and general relativity theory. It presents them in layman's terms and explains how these theories all work (or don't work) together.
From the Paper
"Quantum mechanics or the quantum field theory has worked well to describe the known behaviors and properties of particles of the Planck length or very small particles. General Relativity works with large objects like planets and galaxies. However the theories only works when one of the two theories can be neglected. General relativity has explained a lot about the universe, the evolution of stars, the orbits of planets, and best-known theory ?the Big Bang?. It also shows how black holes and gravitational forces work. However, the General relativity theory only works on its own and when we think of the universe in traditional matter because of the fact that quantum mechanics dose not comply the description of General Relativity. The two work well to explain the theories they were set up to explain however the do not work together. String theory was then conceived to explain the how Quantum Mechanics, the really small stuff, and General Relativity, the really large stuff, works together."
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Radiation Safety, 2004.
This paper discusses the uses of radiation and safety measures that can be taken to protect from overexposure.
3,080 words (approx. 12.3 pages), 10 sources, MLA, $ 90.95
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Abstract
This paper explains that it is next to impossible to avoid sources of natural radiation in our everyday life, but precautions can be taken to maintain distance from local sources of radiation and to use distance, time, and radiation-shielding as protection. The author points out that radiation is not responsible for the assumed mechanism of carcinogenesis caused by the exposure to magnetic fields. The paper relates that the nuclear industry and many other sources of radioactivity are used in an enormous range of industrial processes, such as industrial radiography, thickness gauges, smoke alarms, and medical diagnosis and treatment.
Table of Contents
Types and Sources of Ionising Radiation
The Effect of Radiation on the Body
Detecting Radiation
Regulating Body Standards and the Workplace
Ionizing Radiation
Contamination
Stochastic Effects
Deterministic Effects
Monitoring Radiation Exposure
Radiation Accidents
Types of Radiation Accident
The Food Industry Uses Radiation
From the Paper
"Ionising radiation does not accumulate in our body, but science proves that the radiation effects are evident from exposure to large amounts of radiation, as in sunburns from too much exposure to strong sunlight. Radiation carries energy that has a damaging effect on the living cells of living things and can either kill them or change their structure and function to inhibit correct functioning but this would take large doses to kill a good number of cells to cause death. Radiation dose would have to be several thousand times bigger than the dose received annually from the environment to cause death. Death would occur if the person were exposed more over a year. For example, exposure to sunlight over a year gives one a suntan, but one-day exposure of sunbaking could cause death by sunstroke."
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The Stars, 2004.
This paper discusses the composition of stars and the method of studying this composition.
1,445 words (approx. 5.8 pages), 3 sources, MLA, $ 47.95
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Abstract
This paper explains that spectroscopy, the study of the spectral lines of the different atomic constituents, has been one of the oldest and most trusted methods of studying the elemental analysis of stars and other luminous heavenly objects. The author states that, by using spectroscopic observations, the radial velocities and the elemental abundances of the extra galactic objects has successfully been established. The paper reports that the availability of specific spectroscopy software has further hastened the study of the molecular mechanics and quantum mechanics.
Table of Contents
Introduction
Spectroscopy and Study of Stars
Spectral Lines (Elemental Abundance)
Classification according to Spectra
Spectroscopy Software
Conclusion
From the Paper
"The availability of spectroscopic software has allowed the possibility of quick and accurate study of quantum study of the spectral elements. GAMESS is one such software that can be used to calculate the SCF wave functions, perform automatic search for transition states, geometrical orientation and in analyzing the vibrational frequencies. GAMESS (General Atomic and Molecular Electronic Structure System) allows us to integrate quantum mechanics and molecular mechanics, which is essential for our understanding of the complex astronomical science. The software allows us to study chemical functions like dipole movements and to perform complex computations."
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Two Classical Tests of Relativity, 2004.
A brief look at the acceptance of the evidence that led to Albert Einstein's theory of relativity.
1,758 words (approx. 7.0 pages), 6 sources, MLA, $ 56.95
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Abstract
This paper explores how the problem of the anomalous advance of the perihelion of mercury and the bending of light near massive bodies led to one of the most famous theories ever. It discusses the historical context of the two problems and how Einstein's theory was accepted on the strength of the two pieces of evidence. It also looks at how Einstein, when he published his general theory of relativity in 1916, was essentially following the latter method of explaining Mercury?s orbit and how Newton?s inverse square law of gravity was eliminated. Instead, Einstein introduced a gravitational field equation in which energy, as well as mass, could lead to gravitational effects.
From the Paper
"Kepler?s first law of planetary motion states that all planets have an elliptical orbit of the Sun. When orbits are set up as a two body problem involving just the Sun and the planet, the orbit forms a closed ellipse. However, when the influence of the other planets in the solar system is taken into account the ellipse does not form a closed loop. Instead, the perihelion, (point of closest approach to the Sun) precesses around the Sun giving rise to a rosette shaped orbit (see fig 1). This is known as an advance of the perihelion."
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Superconductivity, 2003.
Examines how superconductivity is changing the playing field in the alternative energy field.
1,573 words (approx. 6.3 pages), 4 sources, APA, $ 51.95
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Abstract
While the debate over fossil fuels and global warming continues, scientists are continuing their research into more efficient methods of providing a wide variety of applications, some of which are still being discovered. This paper provides a review and discussion concerning the current status of superconductivity, its existing applications and trends, and trends for the future. This paper includes two relevant graphics.
From the Paper
"Superconductivity consists of the complete disappearance of electrical resistance in various solids when they are cooled below a characteristic temperature. This temperature is called the transition temperature and it varies for different materials but it is generally cited at being below 20 K (-253? C). The phenomenon of superconductivity was first discovered in mercury by the Dutch physicist Heike Kamerlingh Onnes in 1911. However, similar behavior has been identified in approximately 25 other chemical elements (including lead and tin) and in thousands of alloys and chemical compounds. Oher materials that have been studied to within fractions of a degree of absolute zero have consistently demonstrated normal resistance to the flow of electric currents. The use of superconductors in magnets is constrained by the fact that strong magnetic fields above a certain critical value, depending upon the material, cause a superconductor to revert to its normal, or nonsuperconducting, state, even though the material is kept well below the transition temperature (Superconductivity, 2003)."
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Isaac Newton, 2003.
Discusses the scientific and social impact of the scientist's work and theories.
900 words (approx. 3.6 pages), 4 sources, $ 31.95
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Abstract
Describes Isaac Newton's "Principia Mathematica" as the greatest scientific work ever created. Examines his creation of the foundation upon which modern science is built.
From the Paper
"Isaac Newton lived during the scientific revolution of the 17th century. While men like Kepler, Galileo, and Descartes had shaped a new view of nature, Newton organized and expanded all the scientific knowledge..."
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The Solid State Physics of the Light Emitting Diode, 2002.
How LEDs work and their future.
2,006 words (approx. 8.0 pages), 5 sources, MLA, $ 63.95
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Abstract
This paper discusses how light emitting diodes (LEDs) work, materials used to make them, their significance in everyday appliances, and what they may be used for in the future by employing new technologies. The full utility of these devices has not yet been realized; they are highly efficient and have many applications in illumination and storage technology. This paper ?sheds some light? on the many uses for this seemingly simple device.
From the Paper
"Before discussing semiconductors and semiconductor devices we should first cover the basics of conduction. Conductivity of a material is dependent on three factors. First is the number of charge carriers per unit volume or carrier density. Charge carriers can be electrons, holes or ions or any combination thereof. The second factor is the charge per carrier. This is typically measured in Coulombs so it is the elementary charge in the case of electrons and holes or is the charge of the ion in that case. The third factor is the charge mobility. This factor is a little more complicated and will be covered in more depth later. It is dependent, however, on acceleration of the carrier, dependent on electric field strength, and the average time between collisions, which is dependent on temperature and defect concentration. The conductivity is then the product of these three terms."
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Current and Future Trends and Applications in Nanotechnology, 2003.
A comprehensive review of the relevant literature to develop a better understanding of the emerging technology of nanotechnology.
2,287 words (approx. 9.1 pages), 13 sources, MLA, $ 70.95
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Abstract
This paper provides an insight into nanotechnology, an anticipated manufacturing technology that is intended to provide thorough, inexpensive control of the structure of matter through the manipulation of individual atoms. Topics discussed include the definition of nanotechnology, the ultimate goals, and potential hazards of the technology, as well as the companies, both privately and publicly owned, that are involved in the field. It looks at some of the products of nanotechnology and describes how nanotechnology can be used in our daily lives. It also discusses the role the government currently plays in funding research into nanotechnology applications. A summary of the research is provided in the conclusion.
From the Paper
"The term, ?nanotechnology,? was proposed by K. Eric Drexler. The Institute of Nanotechnology advises that nanotechnology can best be considered as a ?catch-all? phrase used to describe activities at the level of atoms and molecules that have applications in real world settings. A nanometer is a billionth of a meter (about 1/80,000 of the diameter of a human hair, or 10 times the diameter of a hydrogen atom) (Nanotechnology ? What Is It?, 2002). Nanomaterials are defined as particles having a size in the range of 1-100 nanometers that exhibit unique physical and electrochemical properties, thereby enabling the manufacture of stronger, harder, more wear-resistant materials."
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Dark Energy, 2003.
An overview of dark energy, the equation of state, and theories of universe expansion.
1,153 words (approx. 4.6 pages), 7 sources, MLA, $ 39.95
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Abstract
This paper describes dark energy, or anti-gravity, and debates theories of universe expansion, touching on Einstein's theory of relativity and cosmological constant. It also talks about the equation of state of the universe and its impact on universe expansion or contraction. It looks at how there are many theories about dark energy from the quintessence theory and the topological defect theory to the cosmological constant theory. It explains that, by analyzing the equation of state of this energy and evaluating current theories, scientists can construe a plausible theory for the fate of the universe.
From the Paper
"Physicists started negotiating and theorizing about the possibility of a dark energy around the turn of the century. One generally un-disproved theory from that time is that which relates the equation of state to the ?cosmological constant?. The cosmological constant (often called lambda) was proposed by Einstein in 1917 to make the universe unchanging in his equations (5). He was generally unsure of this idea, and rejected this theory shortly after it was determined that the universe is perpetually growing. However, his idea of a cosmological constant is currently applied to the universe in a slightly different way, setting the equation of state constant (5)(4). The current theories of dark energy date back to 1998 when supernovae were discovered to be dimmer than expected."
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