Abstract Essays (928 words) - Transducers, Electrical Phenomena

Abstract The experiment involved constructing a microphone from the materials given to us. Our group was supposed to make as sensitive microphone as possible. This laboratory was also intended to introduce the concept of ?sensor? materials which can be made to act as electric sense organs. Our group has lost the competition, but even so by the end of the lab we understood how the microphone works and was able to construct it and test it using the Lab VIEW program. Introduction A real microphone consists of a diaphragm that is connected to a magnet. Sound waves vibrate the diaphragm and move the magnet in and out. The magnet is inside a coil of wire. When the magnet moves inside a coil of wire it produces a voltage signal through the wire. Experimental Work In order to build piezoelectric microphone successfully our group began by thinking of our initial idea for the design. We drew it to the best of our knowledge to get the best results. After that our group got all the necessary parts and began the construction. After a lot of thinking and arguing it was decided to use a small paper cup, aluminum foil, rubber band, scotch tape and of course piezoelectric film. As the parts were put together we made sure that as the sound goes into the microphone it would pick up all the sounds and produce clear result. Then our group made sure that it doesn't fall apart and taped the piezoelectric film to the top of the aluminum foil and tied it together with a rubber band. And only then our group began testing. Our results were not so good, so we began to improve the design by changing the amount of layers of aluminum foil and by trying to cover the top of the paper cup with plastic. Each time our group tried to improve the microphone and tested it, the results were different. Data and Observations Our microphone was constructed using a small paper cup. It was thought by the members of our group that a small cup would help focus the sound in one place. Inside the cup our group has placed layers of aluminum foil, because we thought it would prevent the sound from leaving. At the bottom we made a hall for the piezoelectric film. When our group was observing the printouts from the LABVIEW we looked at both Time Domain and Frequency Domain. Our Time Domain wasn't as high as others, but piezoelectric microphone worked fine and we competed with everyone else. Our Frequency Domain wasn't high either and on the graph you can see two peaks instead of one. Our group also made some observations about the audio. It was difficult to tell the frequency and very difficult to analyze how the microphone responds to certain sounds. It allows people to hear the clarity of a sound produced by a microphone. As far as visual observations, it allows us to analyze the wave the microphone produces. It isn't useful in allowing people to determine how the microphone actually sounds. Conclusion In conclusion I'd like to say that this experiment has taught us not only how to build a piezoelectric microphone, but also about piezoelectric films that we knew nothing about before, and how we can use them in other places. Piezoelectric means composed of crystalline material that when mechanical stress is applied an electric charge is produced. The molecules of crystalline material compress and expand and this causes a voltage to appear at the opposite ends of the film. Some of the places where we might use piezoelectric microphone might be motion detectors, touch-sensitive pads or airbags deployment systems. I think it would be a great idea to use them in airbags deployment systems, because they would be able to tell how short or tall, large or small the person is and adjust the airbag accordingly. I believe this would prevent a lot of injuries. 1. Why can piezoelectric film be used as a sensor? Piezoelectric film can be used a sensor because it is sensitive and picks up sounds very easily. If it is located at the right place and surrounded by the right environment it can pick up noises that are hard to hear and vibrate. 2. What

Julius Caeser Essays - Ancient Rome, Roman Republic, Free Essays

Julius Caeser.txt Essays - Ancient Rome, Roman Republic, Free Essays Julius Caeser Gaius Julius Caesar, a patrician and noble, became one of the most powerful men in Ancient Roman history. Caesar was a populare1, and eventually became the people's hero. His leadership qualities gained him the consulship of 59 B.C., and eventually perpetual dictatorship. Caesar's acquired power soon became immense, and soon the ruling class began to fear his power. This wealth of power brought back images of the ruthless Roman monarchy, abolished centuries before, in 510 B.C. Caesar presided over the military, politics and religion; it allowed him to virtually control Rome. And, it was eventually Caesar's power which led to his demise on the Ides Of March in 44BC. CAESAR'S POWER Caesar gained power in three main areas which dominated Roman life. He acquired power in politics and the government, in religion2, and in the military3. Using his power in these posts, his established a form of rule through which he could control many aspects of Roman life. On July 25th, 46B.C., Julius Caesar secured the office of Dictator4 for ten years. It was here, that Caesar found his power to preside over others, and where he became passionately hated by the Roman ruling class. As dictator, Caesar had secured the power of an absolute ruler. Earlier that year, he had been given Censorial powers, as the 'Director Of Public Morals' (praefectura morum)5. The dictatorship now meant that he had the powers of all the other offices in the Cursus Honorum.6 Caesar wanted to make reforms to improve life in Rome. However, he needed the Senate's help to pass legislation. The Senate had been one of the main problems for Caesar's predecessors. They had obstructed the passage of laws which would have benefited the state. However, Caesar was determined to not be presided over by the Senate. The civil war against Pompey had taken a toll on the Senate. Many of Pompey's supporters who were Senators, had been killed in battle. In addition, Caesar had increased the number of Senators from five to six hundred, to about nine hundred. To fill the vacant seats, he selected the Senators from a range of places7 and occupations. The new senators were all supporters of Caesar8, and vastly outnumbered the old senators.9 Effectively, the Senate became nothing more than a puppet of Caesar's power. As Caesar was dictator, his Imperium power was greater than any of the magistrates, even the consuls. He had gained many rights, as dictator which also allowed him to control the magistrates, and their elections. During Caesar's rule, elections into office proceeded as normal. However, he had passed legislation which allowed him to control the elections10, whereby his suggestions were always acknowledged. In this manner, many of his colleagues were rewarded with posts as magistrates. Prior to Caesar, the consuls had been the most respected and powerful of the political magistracies. Now, it had been turned into an insignificant parody of its former use. Cicero makes comment about the way in which Caesar had converted political office into a 'sad joke' - "At one o'clock, Caesar announced the election of a consul to serve until 1 January - which was the next morning. So I can inform you that in Canninus' consulship, nobody had lunch. Still, nothing untoward occurred while he was consul: such was his vigilance that throughout his consulship, he did not sleep a wink!" 11 His further comment, also showed his opinion of what Caesar had turned the political magistracies into: "...you could not help but weep... there are countless similar instances.12" The dictatorship was the one thing which was constitutional about Caesar's rule. However, "in him [Caesar], the awed respect for constitutional niceties with which so many of his fellow Romans were imbued, seems to have been totally lacking.13" And then in February of 44BC, he was named Dictatus Perpetuus. Being dictator for life, now meant that Rome had effectively reverted to absolute control - what the republicans had feared for. His term as dictatus perpetuus also granted him rights which made him invulnerable to constitutional safeguards. Now, the veto of the tribunes14 couldn't affect his legislation or decisions. One of the safeguards of the constitution of the Republic had been removed15; and thus autocracy became one step closer. DICTATOR, AUTOCRAT & MONARCH ? Caesar's