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Paper On Magnets

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There is not much that can be done without the use of magnets. The obvious uses are in hospitals with MRI machines, in our car and mobile phone speakers so we can hear our calls and enjoy our music. However, the use of magnets in nearly all electronics is often overlooked. Electronics need magnets to run, whether it’s a vacuum cleaner, the windows in a car, or the office telephone. Although men lived and worked at one time without magnets, it is impossible today. Living, working and relaxing today would be nearly impossible to do without magnets.
History of Magnets Magnets were likely discovered by a shepherd named Magnes in Greece. What he found were loadstones, which contain magnetite, (Fe3O4) which is a natural magnetic material. …show more content…

While a permanent magnet causes repulsion with one pole when the poles are brought in turn near a suspended magnet, an unmagnetized magnet material would be attracted to both poles. A piece of steel can be made into a magnet by stroking it with one or two magnets. It can also be done electrically, using a solenoid and 6-12 V d.c. current. Switch on the current for a second and then off. Remove steel from solenoid - the steel will be a magnet. The polarity produced depends on the direction of the current. Using the Right-Hand Grip Rule shows the polarity: if the right-hand grips the solenoid, placing fingers on one by one in the direction for the current, positive to negative, the thumb will point to the north pole. Magnets produce a magnetic field which can be recognized with a compass. The needle of a compass will always allineate with the magnetic field. The Earth has its own magnetic field which is what magnetizes lodestones. The Earth’s north magnetic pole is nowhere near the geographic north pole, it is instead near the geographic south pole. This is because, “The north pole of a magnet is attracted to the south pole of a second magnet and the north pole of a compass needle points to the earth” (Ostdiek & Bord, …show more content…

While walking or riding a bike to work is great for the environment, it is not always the best mode of transportation if you want to get to work on time. Usually, we need to drive to work, school or to the gym or at least catch the bus. However, this cannot be done without magnets in the solenoid to engage the starter motors! On a scorching day, we all like the refreshing chilliness in our air-conditioned homes and watch a movie on Netflix or perhaps play Okami on our Nintendo Wii. Yet, we cannot even do these without magnets. Putting the groceries away in the refrigerator, mixing up the cake for dessert, compacting the trash or starting the dishwasher are all things we would not be able to do without magnets. We do not only need magnets to make our lives nicer and simpler, but also for our health and for industry. “The discovery of a relationship between electricity and magnetism made possible the invention of the electric motor” (Electric Motors, 2008). Without one or more fixed magnets combined with a movable current-carrying coil, electric motors will not run. Pinball machines, paintball markers, dot matrix printers and fuel injectors in vehicles all use magnets by means of electromechanical solenoids. A solenoid is “a tightly wound helix of current-carrying wire (which) acts like a hollow bar magnet” (Electricity and Magnetism,

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