Transcript Magnets
The Science of Disney Imagineering THE SCIENCE OF MAGNETISM In this video, students in grades 5 through 8 join Disney Imagineer, Asa Kalama, on an E-ticket ride into the world of imagination, inspiration, and science—the science of magnetism. Asa travels to Disney’s theme parks to show students how magnetism is put to work as they design and build amazing attractions, such as Pirates of the Caribbean and Rock ’n’ Rollercoaster. The Science of Magnetism Preview Questions 1.What is magnetism? 2.What are some characteristics of magnets? 3. In what ways do you use magnetism in everyday life? 4.Why do you think magnets have properties of attraction and repulsion? The Science of Magnetism Post-viewing Questions 5.What makes a magnet a magnet? 6.What is a magnetic field? 7.What is a permanent magnet? 8.What is an electromagnet? Magnetism Notes Page 1 • Magnetism is the force of attraction or repulsion. • A magnet is any object that exhibits the magnetic properties of attraction and repulsion. • Ferromagnetic metals , such as iron, are strongly attracted to magnets and can become magnets. Magnetism Notes Page 2 • Magnets can be human-made in all different shapes, sizes, and strengths. • Every magnet has two poles—north and south— where the attraction is strongest. • Opposite poles attract; like poles repel. Magnetism Notes Page 3 •Earth’s geographic north is its magnetic south pole; its geographic south is its magnetic north. •Every magnet has a magnetic field that runs in a loop from north to south poles, through the magnet, and around and around. •When like poles are put together, they repulse each other as they try to make their field lines line up in the same direction. Magnetism Notes Page 4 • Everything is made of atoms, which have a positively charged nucleus and negatively charged electrons orbiting the nucleus. When electrons move, they create a magnetic field. • In the atoms of most materials, pairs of electrons spin in a way that cancels the magnetic field. • Electrons in magnets spin by themselves, with nothing to cancel the magnetic field. Magnetism Notes Page 5 • Magnets stick together because they align their fields to make bigger magnets. • Clumps of magnetic atoms are called domains. • Permanent magnets are always attracting and repulsing. Magnetism Notes Page 6 • An electromagnet is a temporary magnet that becomes a magnet when electricity is applied. • An electric motor uses electromagnets placed around permanent magnets. • Magnetism can be used to do things as varied as hold things together, propel vehicles down a track, and produce sounds through audio speakers. MAGNETS Enrichment Activities • http://www.harcourtschool.com/activity/electromagnets/ • http://www.harcourtschool.com/activity/science_up_close/504/deploy/int erface.html • Exploratorium • http://www.exploratorium.edu/snacks/iconmagnetism.html • How Stuff Works: How Electromagnets Work • http://www.howstuffworks.com/electromagnet.htm • How Stuff Works: How Magnets Work • http://science.howstuffworks.com/magnet.htm • NOVA: Magnetic Storm • http://www.pbs.org/wgbh/nova/magnetic/ TEST YOUR KNOWLEDGE OF MAGNETISM 1 A metal that is strongly attracted to a magnet is called ____. 2 Steel is an example of a ferromagnetic material. -------3 Every magnet has ___ where the attraction is strongest. 4 The rule for magnetic poles is : “ like poles ___; opposite poles ___.” 5 Earth has two magnetic poles. 6 Earth’s geographic north pole is _____. 7 Electrons are tiny _______. 8 In the atoms of most materials, pairs of electrons spin in a way that cancels the magnetic field. 9 A clump of magnetic atoms is called a _____. 10 If you cut a magnet into small pieces, the small pieces are no longer magnetic. 11 This type of magnet is always attracting and repulsing. 12 An electromagnet is a ____ magnet. 13 When electrons move, they create a _____. 14 You can make an electromagnet by coiling a wire around an iron rod. 15 An electromagnet becomes a magnet when electricity is turned on. TEST YOUR KNOWLEDGE OF MAGNETISM ANSWER KEY 1 A metal that is strongly attracted to a magnet is called ____. Ferromagnetic 2 Steel is an example of a ferromagnetic material. true 3 Every magnet has ___ where the attraction is strongest. two poles 4 The rule for magnetic poles is : “like poles ___; opposite poles ___.” repel; attract 5 Earth has two magnetic poles. true 6 Earth’s geographic north pole is _____. it’s magnetic south pole 7 Electrons are tiny _____. magnets 8 In the atoms of most materials, pairs of electrons spin in a way that cancels the magnetic field. true 9 A clump of magnetic atoms is called a _____. domain 10 If you cut a magnet into small pieces, the small pieces are no longer magnetic. false 11 This type of magnet is always attracting and repulsing. permanent magnet 12 An electromagnet is a ____ magnet. temporary 13 When electrons move, they create a _____. magnetic field 14 You can make an electromagnet by coiling a wire around an iron rod. true 15 An electromagnet becomes a magnet when electricity is turned on. true