Chromium
.... be increased by adding small quantities of chromium to it. Chromium steel
alloys (mixtures containing one or more metals) are used to make armor plating
for tanks and warships. They are also used for ball bearings and the hard
cutting edges of high-speed machine tools.
Nickel is highly resistant to electric current and is often added to
chromium steels to make them easier to work. For example, stainless steel
sinks can be pressed out from flat sheets of steel that can contain 18 percent
chom .....
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Collisions Of Two Objects
.... the same before and after impact, the
coefficient is equal to 1, and the collision is elastic. In practice, however,
such perfectly elastic collisions occur only on an atomic scale; most collisions
are therefor not elastic, with a coefficient of restitution of less than 1.
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Comets
.... the nucleus of a comet
slightly away from its otherwise predictable path. In addition, short-period
comets, observed over many revolutions, tend to fade very slowly with time, as
would be expected of the kind of structure proposed by Whipple. Finally, the
existence of comet groups shows that cometary nuclei are fairly solid units. The
head of a comet, including the hazy coma, may exceed the planet Jupiter in size.
The solid portion of most comets, however, is equivalent to only a few cubic
kilometers .....
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The Cosmos: Creation
.... Hubble saw this and concluded that all galaxies are rushing away from us and
the universe is expanding as a whole. Modern equipment has observed and
verified this so-called Hubble expansion exists throughout the observable
universe.
This shows three important things. First there is no significance to the
fact that earth seems to be the center of the universal expansion. In any
galaxy it would look as if you were standing still and all others were rushing
away from you. Second the movement .....
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Cryogenics And The Future
.... liquid oxygen in his lab using a process known as
adiabatic expansion, which is a "thermodynamic process in which the temperature
of a gas is expanded without adding or extracting heat from the gas or the
surrounding system"(Vance 26). At the same time Pictet used the "Joule-Thompson
Effect," a thermodynamic process that states that the "temperature of a fluid is
reduced in a process involving expansion below a certain temperature and
pressure"(McClintock 4). After Cailletet and Pictet, a third method, .....
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Radio Waves
.... frequencies are measured in units called kilohertz, megahertz, and
gigahertz. (1 kilohertz = 1000 hertz : 1 megahertz = 106 hertz, 1 gigahertz =
109 hertz). All radio waves fall within a frequency range of 3 kilohertz, or
3000 cycles per second to 30 gigahertz. Within the range of frequencies, radio
waves are further divided into two groups or bands such as very low frequency (
VLF 10-30 kHz ), low frequency (LF 30-300 KHz), medium frequency ( MF 300-3000
KHz), high frequency ( HF 3-30 MHZ) and very high .....
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Does Life Exist On Mars
.... from on earth. I do see the possibility that maybe other
solar systems is our solar system in history which is an interesting thought.
Just because NASA has found a single cell living creature in a meteorite doesn't
prove anything in my mind. Especially because of the fact that it has been on
earth for 12 years when over this time the cell could have attached itself to
the meteorite.
Nobody knows enough about the subject to start telling the public that this is
true, they should have never released it un .....
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Earthquakes
.... as body waves—that is, they travel through the
earth's interior—and the other four are surface waves. The waves are further
differentiated by the kinds of motions they impart to rock particles. Primary or
compressional waves (P waves) send particles oscillating back and forth in the
same direction as the waves are traveling, whereas secondary or transverse shear
waves (S waves) impart vibrations perpendicular to their direction of travel. P
waves always travel at higher velocities than S waves, s .....
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Fiber Optics
.... of light through hair-thin glass fibres.
The clear advantages of fibre optics are too often obscured by concerns that
may have been valid during the pioneering days of fibre, but that have since
been answered by technical advances.
Fibre is fragile
An optical fibre has greater tensile strength than copper or steel fibres of the
same diameter. It is flexible, bends easily, and resists most corrosive
elements that attack copper cable. Optical cables can withstand pulling forces
of more than 150 pou .....
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The Geiger-Muller Tube
.... registers the arrival of
a particle by advancing a counter or producing an audible signal, such as a
click. The potential difference across the tube so that the current flow stops.
Thus the tube is ready for the beginning of a new avalanche when another
particle or gamma ray enters it.
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The Space Shuttle
.... two commercial communications satellites from November 11 to 16, 1982.
Later memorable flights included the seventh, whose crew included the first U.S.
woman astronaut, Sally K. Ride; the ninth mission, November 28-December 8, 1983,
which carried the first of the European Space Agency's Spacelabs; the 11th
mission, April 7-13, 1984, during which a satellite was retrieved, repaired, and
redeployed; and the 14th mission, November 8-14, 1984, when two expensive
malfunctioning satellites were retrieved and ret .....
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Fern Life Cycle
.... spore wall and observed how the
developing gametophyte had broken through the wall, as instructed by our lab
manuals. One could also identify the chloroplasts with in the cell. We then put
up our dishes for another week.
The third week of our fern lab we identified the difference between male
and female gametophytes. We did this by taking a culture from our petri dish and
placing it under a dissecting microscope. Due to the male and female being both
located on the same prothallus it was necessary to .....
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Voltage: Ohm's Law And Kirchhoff's Rules
.... resistance is, RTOTAL=R1+R2+ ..... +Rn .
And for resistors connected in parallel, 1/RTOTAL==1/R1+1/R2+ ..... +1/Rn .
Complex dc circuit involving a combination of parallel and series resistors can
be analyzed to find the current and voltage at each point of the circuit using 2
basic rules formulated by Kirchhoff. 1) The algebraic sum of current at any
branch point in a circuit is zero. 2) The algebraic sum of potential difference,
V, around any closed loop in a circuit is zero. These rules and equation .....
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What Is Physics And What Are Its Uses?
.... breakthroughs because of principles
of physics. Doctors are now able to use lasers for surgery. Lasers are based
on the physical principle of light, and are devices for the creation and
amplification of a narrow, intense beam of coherent light. New laser
microsurgery can actually alter the shape of the cornea in the eye so the
patient's eyesight can return to normal, and he/she will no longer need those
bothersome glasses. Ultrasound is used in the medical field for destroying
various unwanted subs .....
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The Laser
.... 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 .....
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