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Download Lesson 1 Magnets
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Do now! You have 2 minutes to play with your magnets. What do you need to know about magnets? ALL magnets have two poles NORTH seeking pole SOUTH seeking pole Breaking a magnet produces two magnets! N N S N S S N S Opposites attract! Opposite poles attract and like poles repel Magnetic materials Magnetic materials Iron (steel), Cobalt and Nickel Magnetic induction Magnetic induction When a magnetic material is close to a magnet, it becomes a magnet itself magnet S N S We say it has induced magnetism N Hard and Soft Magnetism Soft Magnetism Pure iron is a soft magnetic material before S N S after N S NN Not a magnet Iron nail It is easy to magnetise but loses its magnetism easily Hard Magnetism Steel is a hard magnetic material before S after N S S N NN S N It’s a magnet! Steel paper clip It is harder to magnetise, but keeps its magnetism (it is used to make magnets!) Magnetic fields I wonder if this is a magnetic field? Magnetic fields Magnets (and electric currents) produce magnetic fields around them. In the magnetic field, another magnet or magnetic material will experience a magnetic force. Magnetic field lines We can represent the magnetic field around a magnet using field lines. Magnetic field lines The arrows show the direction a compass needle would point at that point in the field. Magnetic field lines The arrows show the direction a compass needle would point at that point in the field. The closer the field lines are, the stronger the magnetic force felt Field around a bar magnet Earth’s Magnetic Field Remember the North of a compass needle points to the geographic north pole (i.e. the geographic North pole is a magnetic south pole!) Draw the sentence Draw the sentence 1. Magnets ALWAYS have two poles, North and South. 2. Opposite poles attract, and like poles repel. 3. Iron (steel), cobalt and nickel are the only elements that are attracted to magnets. 4. When a magnetic material is close to a magnet, it becomes a magnet itself. 5. Iron is a SOFT magnetic material;it is easily magnetised but easily loses its magnetism. 6. Steel is a HARD magnetic material; it is hard to magnetise but keeps its magnetism. 7. The magnetic field around a bar magnet is shaped like a burger, with lines and arrows going from N to S. 8. Nottingham is the home of good football.