What is a Hydrogen Bomb

A hydrogen bomb is, by far, the most destructive weapon that mankind has ever invented. It is the most powerful type of nuclear bomb, as much as 25,000 times the yield of the nuclear bombs dropped on Hiroshima and Nagasaki, Japan. Unlike conventional atom bombs (also known as A-bombs), which release energy by fissioning (breaking apart) heavy atomic nuclei like uranium and plutonium, a hydrogen bomb releases energy by fusing together light nuclei like tritium or deuterium, converting even more matter into energy. When Truman authorized the dropping of the A-bomb on Hiroshima and Nagasaki, he said that the weapons used the same power that the Sun did, but that wasn't actually true -- the Sun uses nuclear fusion, not nuclear fission. Thus, a hydrogen bomb really does release the power that fuels the Sun.

The largest nuclear bombs, and the backbone of the nuclear arsenal of the United States and Russia, are hydrogen bombs. These bombs work using a two-stage design whereby a fission bomb "primary" is detonated using the conventional implosion method, which then compresses a fusion fuel "secondary" and ignites a uranium "spark plug" which fissions and subjects the fusion fuel to the heat necessary to begin a chain reaction -- about 20 million degrees F. The light nuclei fuse together into heavier elements, releasing tremendous energy from the strong nuclear force that binds their constituent particles together.

As a result of using fusion rather than fission, the bomb yield is much higher. In fission bombs, approximately 0.1% of the mass of the fuel is converted directly into energy, while in fusion bombs, this ratio is slightly improved, on the order of 0.3%. The first time the principle of a hydrogen bomb was tested was on 9 May 1951 by the United States military, during the George shot of Operation Greenhouse at the Pacific Proving Grounds. Most of the yield of this test came from fission fuel, but it tested the idea that a fission bomb could be used as a stepping stone to something even more destructive. A similar test, Item, took place on 25 May 1951.

The first true hydrogen bomb test, Ivy Mike, was on 1 November 1952, detonated at Enewetak Atoll in the Pacific, as part of Operation Ivy. The bomb exploded with a force equivalent to 10.4 megatons of TNT (over 450 times more powerful than the atomic bomb dropped on Nagasaki during WWII). Using liquid deuterium as fuel, this hydrogen bomb required 18 tonnes of refrigeration equipment to keep the deuterium in liquid form. A later test, Castle Bravo, used solid lithium deuteride instead, decreasing the weight of the device and making it a practical weapon. The Castle Bravo shot is the most powerful nuclear weapon ever tested by the United States, with a yield of 15 megatons.

Today, all of humanity is still put at risk by a nuclear winter initiated by hydrogen bombs.

How Can I Play the Music on my Computer Through my Stereo

Music files have revolutionized the way people listen to and archive music. Soft MP3 players, or software designed to play music files, have made it easy and convenient to build ad-hoc playlists for any occasion or mood. Although programmable compact disk (CD) players allowed some flexibility to create playlists, the ease of clicking to add tunes to a software interface makes other forms of programming feel downright archaic and restrictive by comparison. It’s no wonder then that people want the option of using soft MP3 players to listen to music files through the main stereo system or entertainment center. Luckily, it’s an easy thing to do, and it can be done wired or wirelessly.

The most common and least expensive way to route music from your computer to your stereo system is to run an RCA audio cable from the sound card on the computer to the stereo receiver. All sound cards are made with at least one Line Out jack, used to power computer speakers. The jack is normally a 3.5mm mini phone plug. An inexpensive adapter that features a 3.5mm stereo jack at one end, and two female RCA jacks at the other will work well here. This will connect to a standard RCA stereo cable. The opposite end of the cable will plug into the stereo or surround sound receiver. Here you’ll need an available Audio Line In RCA port, which may be marked Aux for auxiliary. 

After the connection is made, set the volume down before powering up the receiver. Change the receiver mode to auxiliary (rather than tuner, CD, DVD, TV, etc.), and slowly turn the volume up. You may need to boost the volume control of soft MP3 player as well. 

Advanced sound cards might also have other Line Out options, such as Digital Out. The instructions are the same, substituting a digital cable for the RCA cable. The receiver will also need a Digital Audio-In port.

Though wired methods are inexpensive, they have the disadvantage of requiring a physical cable to run from the computer to the stereo system. If the computer is a desktop located in a different room from the stereo or entertainment center, this can be impractical. A laptop provides a good mobile medium for music libraries, as it can be set rather close to the stereo system to simplify things and keep wires out of walkways.

When hard wiring your music connection isn’t practical, another method is to go wireless. In this case a small transmitter is connected to the Line Out port of the sound card, and a matching receiver is connected to the Audio Line In port of the receiver. Music from the computer is silently broadcast via radio waves from the transmitter to the receiver. The receiver interprets the radio signals and translates them back into an audible signal to play through the speakers of the entertainment center. 

Wireless stereo transmitters vary in design and pricing and a few models are expressly designed for iTunes music. Others include composite video ports to send not just audio, but video signals between the computer and entertainment center. Cables might be included or sold separately. For more information check your local electronics stores or your favorite online retailers. 

What Is Teflon®

Teflon® is a brand of polytetrafluoroethylene (PTFE), a solid polymer that is considered to be one of the world's most slippery substances. Accidentally invented in 1938 a laboratory in Deepwater, New Jersey, in the United States, Teflon® has applications in a wide range of areas, including household goods, the aerospace industry, electronics and industrial processes. Teflon® is produced by E.I. du Pont de Nemours and Company, also known as DuPont.

History

PTFE is a fluorocarbon, a compound made up of carbon and fluorine, and it has the molecular formula (C₂F₄)n. A chemist named Roy Plunkett accidentally invented PTFE while trying to create a new chlorofluorocarbon in a New Jersey laboratory operated by Kinetic Chemicals Inc., a company that was co-founded by DuPont and General Motors. Plunkett discovered that the white, wax-like substance that was created during one of his experiments was extremely slippery and water-resistant. The substance was patented in 1941, and the Teflon® trademark was registered in 1945.

Qualities

Teflon® has a coefficient of friction against polished steel of 0.05 to 0.1, which is one of the lowest for any solid that has been measured. This makes it suitable for use in applications that require reduced friction between two solids, such as gears or sliding parts. It also is hydrophobic, which means that it repels water instead of getting wet. Among PTFE's other qualities that make it beneficial for many uses are its high melting point and its electrical insulating properties.

Uses

In the 21st century, in addition to its widespread use in manufacturing and industry, PTFE is used on all sorts of everyday items. Many people are familiar with non-stick cooking pots and pans that have been coated with Teflon®. Automobile wiper blades also are commonly coated with PTFE, which helps keep the blades from squeaking as they pass back and forth across the windshield. PTFE also is used as a carpet or fabric protector because it repels liquids, allowing spills to be wiped up without leaving a stain. It has been used on all-weather clothing, to coat eyeglass lenses, as a fingernail protector and even in a line of haircare products.

Safety

There has been some concern about the safety of PTFE, especially in cookware. In the U.S., the Environmental Protection Agency (EPA) and Food and Drug Administration (FDA) have stated that the use of this coating on cookware and other items commonly used by people does not pose a concern. DuPont has said that Teflon® coatings do begin to deteriorate at or above 500° Fahrenheit (260° Celsius), a temperature higher than that at which most foods are cooked. Teflon®-coated pans are not recommended for cooking techniques that require very high temperatures, such as broiling.

What is an Embryo

An embryo is an organism in the early stages of development which cannot survive on its own. The precise definition of an embryo varies; in humans, for example, a fertilized egg may be considered an embryo until around the eighth week of pregnancy, at which point it is termed a fetus. The study of embryos is known as embryology, and it makes up part of a larger branch of science which is interested in reproduction and development.

The term “embryo” is only used to refer to eukaryote organisms, otherwise known as multicellur organisms. Typically, people use the term specifically to refer to diploid eukaryotes, meaning that the embryo has a complete set of genetic material from two donors. This genetic material takes the form of haploid sperm and eggs; a haploid cell only contains half a set of chromosomes, meaning that it cannot develop into anything unless it is combined with another haploid cell. As an embryo matures, it starts to turn into a recognizable form, at which point people may start referring to it as a fetus, especially in humans.

The formation of an embryo starts at fertilization. When eggs and sperm meet, they form what is known as a zygote. A zygote is a single diploid cell, created through the merging of two haploid cells. After fertilization, the zygote starts to divide, laying the groundwork for the mature organism which will eventually be born, hatched, or grown. When division begins, a zygote turns into an embryo.

Embryos cannot survive independently because they lack the tissues, body structure, organs, and so forth needed to do so. The parent of an embryo must feed it and watch out for it until it reaches viability. In mammals, this is accomplished by incubating the embryo inside the body and nourishing it with nutrients from the parents. Plants and egg laying animals provide the embryo with a rich layer of nutrients encased in a hard shell which will protect it until it is ready to be born.

The status of embryos is rather complex. Some people feel that an embryo is a life form, since it represents the potential of a living organism. Others do not regard embryos as lives, since they cannot survive on their own, and in the early stages they do not resemble anything familiar. This debate has led to conflict in some parts of the world, especially when it comes to human embryos and the choice to terminate a pregnancy.

What Is Rust

Rust is another name for iron oxide, which occurs when iron or an alloy that contains iron, like steel, is exposed to oxygen and moisture for a long period of time. Over time, the oxygen combines with the metal at an atomic level, forming a new compound called an oxide and weakening the bonds of the metal itself. Although some people refer to rust generally as "oxidation," that term is much more general; although rust forms when iron undergoes oxidation, not all oxidation forms rust. Only iron or alloys that contain iron can rust, but other metals can corrode in similar ways.

The main catalyst for the rusting process is water. Iron or steel structures might appear to be solid, but water molecules can penetrate the microscopic pits and cracks in any exposed metal. The hydrogen atoms present in water molecules can combine with other elements to form acids, which will eventually cause more metal to be exposed. 

If sodium is present, as is the case with saltwater, the corrosion is likely to occur more quickly. Meanwhile, the oxygen atoms combine with metallic atoms to form the destructive oxide compound. As the atoms combine, they weaken the metal, making the structure brittle and crumbly.

Some pieces of iron or steel are thick enough to maintain their integrity even if iron oxide forms on the surface. The thinner the metal, the better the chance that rusting will occur. Placing a steel wool pad in water and exposing it to air will cause rusting to begin almost immediately because the steel filaments are so thin. Eventually, the individual iron bonds will be destroyed, and the entire pad will disintegrate. 

Rust formation cannot be stopped easily, but metals can be treated to resist the most damaging effects. Some are protected by water-resistant paints, preventative coatings or other chemical barriers, such as oil. It also is possible for one to reduce the chances of rust forming by using a dehumidifier or desiccant to help remove moisture from the air, but this usually is effective only in relatively small areas. 

Steel is often galvanized to prevent iron oxide from forming; this process usually involves a very thin layer of zinc being applied to the surface. Another process, called plating, can be used to add a layer of zinc, tin or chrome to the metal. Cathodic protection involves using an electrical charge to suppress or prevent the chemical reaction that causes rust from occurring.

What is a Metric Ton

A metric ton is a unit of measurement based on the metric system, rather than the standard system used in the United States. A metric ton is equivalent to 1,000 kilograms, and is strictly speaking a megagram, being one million grams.

The word most likely comes from the Latin word tunna, which is a word for a cask. Since a large cask full of something would weigh roughly a metric ton, this origin is commonly accepted. The word has been in use for quite some time, although previously the spelling was more often tunne.

The metric ton is often spelled as tonne, and in the United States may also be called a tonneau. A metric ton is not to be confused with the short ton unit, known simply as a ton in the system used in the United States. This ton is equal to 2000 pounds, or roughly 907kg. It should also not be confused with a long ton, a unit no longer in common usage in the United States, which is equal to 2240 pounds.

The official symbol for the metric ton in the International System of Units (SI) is simply ‘t’. Although all of the standard prefixes can be used with the metric ton, in practice the most common ones are the same ones used with the short ton. The kilotonne and megatonne are the only two units commonly seen outside of the metric ton itself. 

Kilotonne and megatonne may be used as metric for measuring energy release. This makes use of the metric ton by connecting it with the explosive TNT, as a way of calculating the force of an explosion. A metric ton of TNT releases roughly 4.19 X 10^9 Joules of energy, with a kilotonne releasing 4.19 X 10^12, and a megatonne releasing 4.19 X 10^15. To put this in some context, the Hiroshima bomb was equal to about twenty kilotonnes of TNT, while a modern nuclear missile could fall closer to the twenty megatonne range.

Because of the similarity in pronunciation — and in some circles, spelling — there can often be confusion between a short ton, a long ton, and a metric ton. In general, in the metric-using world the term ton or tonne alone will be used to refer to a metric ton, while the distinction long ton or short ton will be used to refer to the measure of the standard or Imperial system. In the United States, the term ton will be used to refer to a short ton, although in some industries — such as freight — a ton may be assumed to be a long ton. The term metric ton is then used to distinguish the metric unit. As a rule of thumb, it is a good idea to distinguish which unit of measurement you intend, if there is any doubt that your listeners might misconstrue your meaning.

What Is Rust

Rust is another name for iron oxide, which occurs when iron or an alloy that contains iron, like steel, is exposed to oxygen and moisture for a long period of time. Over time, the oxygen combines with the metal at an atomic level, forming a new compound called an oxide and weakening the bonds of the metal itself. 

Although some people refer to rust generally as "oxidation," that term is much more general; although rust forms when iron undergoes oxidation, not all oxidation forms rust. Only iron or alloys that contain iron can rust, but other metals can corrode in similar ways.

The main catalyst for the rusting process is water. Iron or steel structures might appear to be solid, but water molecules can penetrate the microscopic pits and cracks in any exposed metal. The hydrogen atoms present in water molecules can combine with other elements to form acids, which will eventually cause more metal to be exposed. 

If sodium is present, as is the case with saltwater, the corrosion is likely to occur more quickly. Meanwhile, the oxygen atoms combine with metallic atoms to form the destructive oxide compound. As the atoms combine, they weaken the metal, making the structure brittle and crumbly.

Some pieces of iron or steel are thick enough to maintain their integrity even if iron oxide forms on the surface. The thinner the metal, the better the chance that rusting will occur. Placing a steel wool pad in water and exposing it to air will cause rusting to begin almost immediately because the steel filaments are so thin. Eventually, the individual iron bonds will be destroyed, and the entire pad will disintegrate. 

Rust formation cannot be stopped easily, but metals can be treated to resist the most damaging effects. Some are protected by water-resistant paints, preventative coatings or other chemical barriers, such as oil. It also is possible for one to reduce the chances of rust forming by using a dehumidifier or desiccant to help remove moisture from the air, but this usually is effective only in relatively small areas. 

Steel is often galvanized to prevent iron oxide from forming; this process usually involves a very thin layer of zinc being applied to the surface. Another process, called plating, can be used to add a layer of zinc, tin or chrome to the metal. Cathodic protection involves using an electrical charge to suppress or prevent the chemical reaction that causes rust from occurring.