Electromagnetism 1 PDF

netism  Objectives: 1. Discuss the history and development of magnetism; 2. Describe the nature of magnet; 3. Identify ways of magnetizing and demagnetizing materials; and 4. Appreciate the importance of electromagnetism in our daily lives. magnetism Electricity is...

netism  Objectives: 1. Discuss the history and development of magnetism; 2. Describe the nature of magnet; 3. Identify ways of magnetizing and demagnetizing materials; and 4. Appreciate the importance of electromagnetism in our daily lives. magnetism Electricity is Magnetism a form of refers to Electricity being the flow of physical energy that moving electrons, it should be phenomena results from known as it produces a arising from the flow of resultant called electrical current. The path that the the force charged electrons flow through is called caused by particles. a circuit. magnets  VOCABULARIES 1. Electromagnetic induction - is the process of using magnetic fields to produce voltage, and in a closed circuit, a current. 2. Electromotive Force or emf- in other words, a voltage. The electric potential produced by either an electrochemical cell or by changing the magnetic field 3. Magnetic field- is the area around a magnet in which there is magnetic force.  VOCABULARIES 4. Magnetic Force - the attraction or repulsion between magnetic poles. 5. Magnetic Poles -the ends of a magnet. 6. Electric Motor - a motor that converts electricity to mechanical work. 7. Electromagnet -a temporary magnet made by coiling wire around an iron core.  VOCABULARIES 8. Ferromagnet - material with a strong attraction to magnetic fields. 9. Circuit -an electrical device providing a path for current to flow. 10. Current - a flow of electricity through a conductor. 11. Ampere - the basic unit of electric current.  netism Hans 182 Christian 0 Oersted -discovered that an electric current can produce magnetic field. netism 18 Michael Faraday and Joseph 31 Henry -discovered that if an electric current can produce a magnetic field, then the reverse is also true- a changing magnetic field can produce electric current, a process called electromagnetic induction.  Magnetism and electricity involve the attraction and repulsion between charged particles and the forces exerted by these charges. The interaction between magnetism and electricity is called electromagnetism. The movement of a magnet can generate electricity. The flow of electricity can generate a magnetic field.  HISTORY OF MAGNETISM ◂ Before the term magnet was used, Greeks called this materials as lodestones. ◂ The name of the district is MAGNESIA where the term magnetism comes from. ◂ The term lodestones was changed to magnet as an appreciation of the place where magnetism originated.  HISTORY OF MAGNETISM ◂ Magnets 1st used for navigation (as compass) by the Chinese. ◂ William Gilbert, Queen Elizabeth’s physician, was the 1st person to make an artificial magnet ◂ He also suggested that the Earth has a magnetic properties because the arrow of a compass always points to the North.  Compass made by William Gilbert, named as Terella means “little earth.” 1st compass used by Chinese for navigation 14  HISTORY OF MAGNETISM ◂ The history of the electric motor begins with Hans Christian Oersted, who discovered in 1820, that electricity produced a magnetic field, as mentioned before. Michael Faraday followed up this in 1821, by devising the principle of the electric motor of his own design.  HISTORY OF MAGNETISM ◂ Andre Marie Ampere, a French physicist, suggested that electric current could exert magnetic force and a current-carrying wire produced magnetic field.  Types Of Magnets Magnets are objects that produce fields that attract or repel other objects  PROPERTIES OF MAGNETS ◂ ALL magnets have both north pole and south pole ◂ Like poles repel; opposite poles attract ◂ Magnetic poles cannot be separated. There is no magnet having only one pole (magnetic monopole). The interaction between electric charges is the electric force while the interaction between magnets is the magnetic force. The magnetic force is due to the two separate regions in the magnet known as magnetic poles. MAGNETIC FIELD  Magnetic Field Characteristics and its Magnetic Field Lines The number The magnetic of magnetic field lines exit field lines from the illustrates the South pole magnetic field and enter the strength. North pole. The field strength is Magnetic fields stronger when converge for lines are closer opposite poles together than and separate for lines are farther like poles placed apart. near each other.  What causes northern lights to form? When the solar wind gets past the magnetic field and travels towards the Earth, it runs into the atmosphere. As the protons and electrons from the solar wind hit the particles in the Earth's atmosphere, they release energy – and this is what causes the northern lights. In the ionosphere, the ions of the solar wind collide with atoms of oxygen and nitrogen from the Earth's atmosphere. The energy released during these collisions causes a colorful glowing halo around the poles— an aurora. The lights are known as 'Aurora borealis' in the north and 'Aurora australis' in the south. Electromagnetism 101 | National Geograp hic – YouTube