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HSC PHYSICS > MOTORS AND GENERATORS| AC & DC
Gather secondary information to discuss the advantages and disadvantages of AC and DC generators and relate these to their use.
AC generators
Advantages
The slip rings of an AC generator have a continuous surface that allows the brushes to remain in contact with the ring’s surface. Thus the brushes in an AC generator do not wear out as fast as in a DC generator as they do not create an electric short circuit every half-turn. Therefore they required less maintenance and is more reliable that DC generators. AC’s voltage can be changed by transformers. It is more readily transformed to different voltages than DC. Because of this property, AC can travel longer distances on
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By 1882, his company was installing DC generators and electric lighting systems. Edison’s company had created many electrical appliances that run on DC such as light bulbs and other home appliances. He had a vested interest in DC as he owned hundreds of DC power stations and all his company's electrical inventions ran on DC.
DC
DC
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& American engineer George Westinghouse bought the USA patent rights for the AC transformer. Tesla’s invention of the induction motor in 1888 largely popularised the commercialisation of AC. o AC induction motors is run by continuously moving a strong magnet back and forth near copper/aluminium that induces eddy currents in the copper/aluminium plate, which will cause it to follow the movement of the magnet – generating rotational kinetic energy. o Because AC induction motors do not require a commutator (as kinetic energy is created by induction), it has the advantage of higher efficiency and lower maintenance as no contact of material is needed. o 90% of motors are AC induction motors – used in fans, hair dryers, fridges, washing machines and vacuum cleaners
AC
AC
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Problems with DC
Power could only be transmitted short distances from the generator because of split ring commutator wore out quickly, higher maintenance reduces efficiency and increased costs there was no efficient method of changing the DC voltage so electricity produced at the
I believe that the Revolution was indeed revolutionary, because of the information that I gathered. The following is an essay composed to explain why I believe that the Revolution was revolutionary.
I was disturbed by the article I read on Medscape because many lives were affected by this physician action. Dr. Fata is an oncologist practicing in Detroit, Michigan who became rich administering excessive or unnecessary chemotherapy to hundreds of patients even to those individuals who did not have cancer (Lowes, 2015). According to federal prosecutors, the excessive and unnecessary treatment, which went beyond chemotherapy was part of a massive criminal scheme that netted at least $17 million from Medicare and private insurers (Lowes, 2015). Dr. Fata performed each actions deliberately which was unethical. He took an oath to provide prudent care to the public which he fail short doing by affecting 553 patients. Besides affecting those individuals
The Breakfast Breakdown The Breakfast Club centers around five students from different “crowds'' spending a Saturday in detention together. A crowd is a large group of young people usually organized around a common shared activity (Steinberg, 2020). The students here come from crowds termed “jocks,” “basketcases,” and “nerds,” etc. The students do not appear to have close friendships with their social groups, making “crowd" a more apt description than “clique.” In fact, by the end of the movie they form a temporary clique (small tight knit group of friends), “The Breakfast Club” (Steinberg, 2020).
Shortly after, the promotion of power grids swept larger cities, in order to be able to use the light bulb, Edison needed support from large grids spanning over the entire country. But Edison’s design was flawed, he was using DC, or direct connect as his main source of power, which only provided electricity over short distances. Where in Europe, people began using a different way of transferring electricity, AC, or alternate connect routes. George Westinghouse, Edison’s rival, adopted and improved on this new technique, eventually setting up his own electric network. This new network would eventually beat Edison, and by the early 1890s, AC became the most used method of transferring electricity.
When the wind is blowing on wind turbines it produces electric power, Fans are old techniques used in the mills and then the water pump, but now it has developed the technology and has become used for electric power production.
Post-traumatic stress disorder (PTSD) is a psychological condition that can follow a traumatic incident (Emory). PTSD can stem from a variety of traumatic events, such as sexual assault, floods, being kidnapped, and major catastrophes like 9/11 (PTSD: A Growing Epidemic). A major symptom of PTSD is re-experiencing trauma by either distressing thoughts or memories, and sometimes by vivid flashbacks in the most severe cases. Other symptoms can include increased anxiety and paranoia, depression, or avoiding situations where flashbacks can be triggered. An estimated 5% of men and 10% of women experience some form of PTSD in their lives (Emory). However, in a smaller demographic, veterans, The U.S. Department of Veterans Affairs have estimated
Around the same time another inventor, George Westinghouse was trying to introduce his alternating current system to the world. Soon after, Tesla was contacted by Westinghouse to purchase all of his patents. Tesla then began working alongside by Westinghouse. However, they ultimately came out victorious with their AC system, Edison was able to bring his system to the market and made his inventions accessible to the world, which Tesla didn’t really do that.
I imagined English 110 to be a sterile while classroom with speckled black on white tile. Instead of a whiteboard, there would be a chalkboard that would like it has been there since the school was established. The room itself would be something one would find in a 1950s film. The professor that would conduct this class was to be some heartless being that would give out a new essay at the end of each lecture and then expect it to be done and ready to be turned in by the next time we had class. Therefore, in my mind, the need to be a writer was not about the creativity but instead getting the job done.
Scouting has been a part of my life for as long as I can remember. I joined in the First grade as a tiger cub and I was super excited. I remember getting my uniform and wanting to wear it everywhere. I was so excited to be a part of it. I have grown up through scouting and can’t picture my life without it. It has shaped me into the man I am today. I am currently working on my Eagle Scout. I want to continue helping the troop even after I finish. I will be involved in scouting for the rest of my life.
Edison also helped improve some inventions other inventors made such as the typewriter, motion picture, electric generator, and the electric powered train (World Book). Edison needed money for all these improvements and inventions, so he had three sponsors who helped fund some of his inventions. His father, J.P. Morgon and the Venderbit family ( History). Edison invested a fair amount of money on his light bulb company, and he spent another half making homes for himself. A large one for him, his wife, and their six children (History).
Nikola Tesla, an engineer and inventor, led the electrical industry to the cutting edge of technology. Tesla's most important invention, alternating current (AC) electricity, remains the global standard of electricity today. He also made major contributions for the X-ray, wireless radio, and devices ranging from microwave ovens to MX missiles.
This means that Tesla won the war of currents with his alternating current. The events that leaded up to this current including Edison’s campaign against AC usage in the United States. In attempt to show how dangerous AC a couple of Edison’s employees created the first electric chair for the state of New York. The International Electro- Technical Exhibition was held in Germany in the year of 1891. This is where the first long distance transmission of a three phase AC was displayed.
Tesla's AC system eventually caught the attention of American engineer and business man George Westinghouse, who was seeking a solution to supplying the nation with long-distance power. Convinced that Tesla's inventions would help him achieve this, in 1888 he purchased his patents for $60,000 in stock and money the Westinghouse Corporation. As interest in an alternating-current system grew, Tesla and Westinghouse were in competition with Thomas Edison, who was intent on selling his direct-current system to the nation. A negative-press campaign was soon waged by Edison, in an attempt to undermine interest in AC power (Nikola tesla biography,
In 1891, at the age of 35, he became a naturalized American citizen. In 1893, at the World's Fair, Tesla and Westinghouse made history by having the first exhibit ever powered by electricity. He demonstrated several things, including the fluorescent light bulb. This was to lead to problems with Edison, as Tesla was in favor of AC power, while Edison was promoting DC power systems.
In 1831, scientist Michael Farday discovered the first form of electricity. He found that when a magnet moved inside a copper coil it created what is known as an electric current. This invention is known as a turbine generator. Even today, in full sized power stations this simple invention is still used and works very effectively. These power stations create mass amounts of energy to turn the turbines. Most of the time the energy is made from the heat, for example when coal is burned. More environmentally friendly power stations use wind or flowing water to turn these turbines. This is known as renewable energy because it will not run out, unlike when oil and coal are used.(3)