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Scientists and magnets
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Introduction
Magnets are stones that produce magnetic fields. The magnetic field is invisible, but is responsible for the most noticeable aspect of a magnet: the attraction of a metal object or the repulsion of another magnet. Magnets are used in common everyday household items: credit cards, TVs, speakers, motors, and compasses. A magnets strength is measured by its magnetic moment. (“Magnetism”)
How did it all begin?
There are legends surrounding the discovery of magnets. One of the more common ones is that an elderly shepherd named Magnes, was herding his sheep in Magnesia, an area in Northern Greece around 4,000 years ago. While he was herding, the nail in his shoes became stuck on the ground where his sheep were grazing. The rock was supposable named either after him or the area where the stone was discovered. ("Canada Science and Technology Museum.")
Another story of magnetism dates back to first century B.C. written by the Greek poet, Lucretius. Many years after its discovery, magnets were thought to posses magical powers; it could cure the sick and ward off evil ghosts. Later, people realized that it attracted iron, and when cut into the shape of a needle or when held by a piece of string, magnets pointed in a north-south direction. It was then called a lodestone, or “leading stone,” because it lead them either north or south. ("Canada Science and Technology Museum.")
Who discovered magnets?
The first time we know about magnets was in 1269, when a soldier named Peter Peregrinus, wrote a letter about everything that was known at that time about a stone called magnetite. It is reported that he was writing this when he was guarding the walls of Lucera, a small town in Italy. It is also reported that, “While people insi...
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.... A drawback of a permanent magnet is once two permanent magnets are placed together it is difficult to separate them. ("Canada Science and Technology Museum.")
Works Cited
"Canada Science and Technology Museum." Background Information for Magnets. Canada Science and Technology Museum, Musée Des Sciences Et De La Technologie Du Canada, Ottawa, CSTM, MSTC. Web. 12 May 2010. .
"Electromagnet." Wikipedia. 13 May 2010. Web. 13 May 2010. .
"Magnetite." Wikipedia. 4 May 2010. Web. 12 May 2010. .
"Magnets." Wikipedia. 10 May 2010. Web. 12 May 2010. .
Rogers, Kirsteen. The Usborne Internet-linked Science Encyclopedia. Tulsa, OK: EDC Pub., 2001. Print.
Auroras have been emitting in our, and other planets’ skies as long as the Solar System has been in motion. In 1619 A.D., Galileo Galilei coined the term "aurora borealis" after Aurora, the Roman goddess of morning. He had the misconception that the auroras he saw were due to sunlight reflecting from the atmosphere. (Angelopoulos, 2008). In 1741, Hiorter and Celsius noted that the polar aurora is accompanied by a disturbance of the magnetic needle. In 1820, Hans Christian Oersted discovered electromagnetism. André-Marie Ampére deduced that magnetism is basically the force between electric currents. In 1851, Samuel Schwabe, a German amateur astronomer, announced the discovery of the 11-year sunspot cycle, and in 1859, Richard Carrington in England observed a violent and rapid eruption near a sunspot; 17 hours later a large magnetic storm began. In 1900-3, Kristian Birkeland experiments with beams of electrons aimed at a magnetized sphere ("terrella") in a vacuum chamber. The electrons hit near the magnetic poles, leading him to propose that the polar aurora is created by electron beams from the Sun. Birkeland also observes magnetic disturbances associated with the aurora, suggesting to him that localized "polar magnetic storms" exist in the auroral zone. In 1958, Eugene Parker (Chicago) proposes the theory of the solar wind. 1981, High resolution images are obtained by Lou Frank's group in Iowa of the entire auroral zone, using the Dynamics Explorer satellite. (Stern & Peredo, 2005) This is the major timeline of how auroras came to be discovered and understood.
During the late 1970's, the world of diagnostic imaging changed drastically due to the introduction of Magnetic Resonance Imaging, also known as MRI. For over 30 years, they have grown to become one of the most significant imaging modalities found in the hospitals and clinics ("EDUCATIONAL OBJECTIVES AND FACULTY INFORMATION"). During its ancient days, these machines were referred to as NMRI machines or, “Nuclear Magnetic Resonance Imaging.” The term “nuclear” comes from the fact that the machine has the capability of imaging an atom's nucleus. Eventually, the term was dropped and replaced with just MRI, because “nuclear” did not sit well with the public view ("EDUCATIONAL OBJECTIVES AND FACULTY INFORMATION"). Many people interpreted the machine to produce an excess amount of radiation in comparison to the traditional X-ray machine. What many of them were unaware of, MRI does not disperse a single ounce of ionizing radiation making it one of the safest diagnostic imaging machine available to this date. MRI machines actually use strong magnetic fields and radio waves to produce high quality images consisting of precise details that cannot be seen on CT (Computed Tomography) or X-ray. The MRI magnet is capable of fabricating large and stable magnetic fields making it the most important and biggest component of MRI. The magnet in an MRI machine is measured on a unit called Tesla. While regular magnets commonly use a unit called gauss (1 Tesla = 10,000 gauss). Compared to Earth's magnetic field (0.5 gauss), the magnet in MRI is about 0.5 to 3.0 tesla range meaning it is immensely strong. The powerful magnetic fields of the machine has the ability to pull on any iron-containing objects and may cause them to abruptly move with great for...
The first compasses in Han dynasty China were made of lodestone, a naturally magnetized ore of iron. The compass was later used for navigation by the Song Dynasty. Later compasses were made of iron needles, magnetized by striking them with a lodestone. Dry compasses begin appearing around 1300 in Medieval Europe. This was supplanted in the early 20th century by the liquid-filled magnetic compass.A number of ancient cultures used lodestones, suspended so they could turn, as magnetic compasses for navigation. Early mechanical compasses are referenced in written records of the Chinese, who began using it for navigation sometime between the 9th and 11th century, "some time before 1050, possibly as early as 850." A common theory by historians, suggests
Students were surprised that the donut magnet and the bar magnets did not attach to each other. They were excited to see that they could manipulate the movement of the donut magnet by using the bar magnets. At this point students were not familiar with attraction and repelling of magnets. To continue with the experiments, one bar magnet was placed on each side of the triangle base to conduct “The Indecisive Magnet” experiment. After students placed their bar magnets around the base of the triangle, they gave the donut magnet, attached to the yarn, a small push.
or by moving a coil of wire inside a magnetic field. One example of a
Magnetism is very useful in our daily life. A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. In addition, magnetic field is a region which a magnetic material experiences a force as the result of the presence of a magnet or a current carrying conductor. Current carrying conductors also known as wire. As we know there have north pole and south pole of a magnet. If same pole of magnet approaches each other, there will repel each other. In contrast, if different pole of magnet approaches each other, they will attract. These are same with the electric charge, if same charge it will repel, different charge it will attract. Although magnets and magnetism were known much earlier, the study of magnetic fields began in 1269 when French scholar Petrus Peregrinus de Maricourt mapped out the magnetic field on the surface of a spherical magnet using iron needles [search from Wikipedia]. Noting that the resulting field lines crossed at two points he named those points 'poles' in analogy to Earth's poles. Each magnet has its own magnetic field which experiences a force as the result of the presence of a magnet and magnetic field has made up of magnetic field lines. The properties of magnetic field lines is it begin at the north pole and end at the south pole. The north pole always flow out while south pole always flow in. The closer the magnetic field lines, the strength of magnetic field increases. Furthermore, these line cannot cross each other. Ferromagnetism is the basic mechanism by which certain materials (such as iron) form permanent magnets, or are attracted to magnets. Ferromagnetic materials...
There are many kinds of batteries which consist of different materials in order to produce an electric charge. Here are some of the most common batteries, what they consist of and how they work.
Rauen (2016) wrote that certification demonstrates that the nurse has the knowledge and skills beyond the basics in the specialty area. The patient, physician, and nurses expect a higher standard when a nurse works in a dedicated field. When a nurse is working in a focused field, more knowledge needs to be obtained to understand the nature and complexity of the disease. The professional certification shows others that there is acknowledgment of quality of care. As hospitals and nurses become more competitive, this standard is raised and consequently a higher quality of care is expected. And, one way of designating high quality of care is through certifications. Professional certification is recognized by American Nurses Credential Center’s (ANCC’s) Magnet Recognition Program for excellence in nursing services. According to the ANCCs (2017), The Magnet Recognition Program’s goals and guiding principles are to promote quality, identify excellence and disseminate best practices. With a hospital having a Magnet status, this will attract and retain top nurses, improve patient care, foster a collaborative culture, and advance nursing standards and practice.
A magnet can be made from different materials, but loadstone is the natural form. The most important part of magnetism to make electric motors work is: A magnet has two different ends, or poles a north and a south pole. These poles behave like electric charges, like poles repel and unlike poles attract although magnets have no affect on still charges. The relationship between electricity and magnetism is that each phenomenon is that each generates a field. Electric fields can be pictured by thinking in terms of gravitational forces. Where, any two objects have a gravitational force one another. Any two electric charges have a force between them (either repelling, or attracting depending on polarity). These electric fiel...
Faraday visualized a magnetic field as composed of many lines of induction, along which a small magnetic compass would point. The aggregate of the lines intersecting a given area is called the magnetic flux. Faraday attributed the electrical effects to a changing magnetic flux.
Usually magnetic fields are created when an electric current is applied to a set of conductive wires wound together (Dixon, 2001). Magnetic fields can also be created using Permanent Magnets (PM). Electrical motors can also work as electrical generators (Correla, 1986). Electrical generators are devices capable of converting mechanical energy into electrical energy. An example would be a wind turbine which works as an electrical generator.
The research that established Faraday as the foremost experimental scientist of his day was, however, in the fields of electricity and magnetism. In 1821 he plotted the magnetic field around a conductor carrying an electric current; the existence of the magnetic field had first been observed by the Danish physicist Hans Christian Oersted in 1819.
Electric currents produce magnetic fields, they can be as small as macroscopic currents in wires, or microscopic currents in atomic orbits caused by electrons. The magnetic field B is described in terms of force on a moving charge in the Lorentz force law. The relationship of magnetic field and charges leads to many practical applications. Magnetic field sources are dipolar in nature, with a north and south magnetic pole. The magnetic field SI unit is the Tesla, it can be seen in the magnetic part of the Lorentz force law F magnetic = qvB composed of (Newton x second)/(Coulomb x meter). The smaller magnetic field unit is the
The effects of electricity control much of our daily lives. Many of our gadgets and everyday tasks are run by this wonderful source of power. For example without electricity we would not be able to make a cup of coffee in the mourning, or even make a long distance call to family or friends. There have been several technological breakthroughs by many brilliant people throughout history regarding electricity. It has come from being discovered as a small current to being transformed into useful power to run such things as computers. Ben Franklin, Guglielmo Marconi, Thomas Edison, Paul Nipkow, and Charles Babbage have all contributed to the advancement of electricity, and all of their advancements have supplied society in many ways.
When you were young, you may have remembered about trying to make objects stick together or move things, like metal paperclips, just by using a magnet. Back then, you probably thought that magnets’ only exist as play things. But, now that you’re older, you’ve realised that these objects play a significant role in day-to-day life.