2. Magnetism Magnetism – the attraction or repulsion of magnetic materials

3. History of Magnetism Magnetism was discovered in Magnesia Greece (which is now Turkey) Magnetism was discovered in Magnesia Greece (which is now Turkey) A mineral in rocks that is magnetic was discovered. This mineral was called magnetite. The name of these rocks are called lodestones. A mineral in rocks that is magnetic was discovered. This mineral was called magnetite. The name of these rocks are called lodestones. Magnetism was discovered in Magnesia Greece (which is now Turkey) Magnetism was discovered in Magnesia Greece (which is now Turkey) A mineral in rocks that is magnetic was discovered. This mineral was called magnetite. The name of these rocks are called lodestones. A mineral in rocks that is magnetic was discovered. This mineral was called magnetite. The name of these rocks are called lodestones.

4. Three Properties of Magnets Allowed to swing freely, one part of a magnet will always point North. Allowed to swing freely, one part of a magnet will always point North. Magnets contain iron and are attracted to materials that are made of iron. Magnets contain iron and are attracted to materials that are made of iron. Magnets attract and repel other magnets. Magnets attract and repel other magnets. Allowed to swing freely, one part of a magnet will always point North. Allowed to swing freely, one part of a magnet will always point North. Magnets contain iron and are attracted to materials that are made of iron. Magnets contain iron and are attracted to materials that are made of iron. Magnets attract and repel other magnets. Magnets attract and repel other magnets.

5. Magnetic Poles All magnets have a North and South Pole. At the poles is where a magnet is the strongest. All magnets have a North and South Pole. At the poles is where a magnet is the strongest. Like poles repel each other. Like poles repel each other. Opposite poles attract each other. Opposite poles attract each other. All magnets have a North and South Pole. At the poles is where a magnet is the strongest. All magnets have a North and South Pole. At the poles is where a magnet is the strongest. Like poles repel each other. Like poles repel each other. Opposite poles attract each other. Opposite poles attract each other.

6. Magnetic Fields The region around a magnet in which magnetic forces act.

7. Magnetic Earth Earth is compared to a bar magnet because it has a magnetic field, poles, and its core consists of iron and nickel.

8. Structure of the Atom Spinning electrons produce a magnetic field. This makes the electrons behave like tiny magnets.

9. Magnetic Domains Magnetic domains are groups of atoms that have their magnetic fields aligned. Magnetic domains are groups of atoms that have their magnetic fields aligned. Magnetized materials have their domains arranged in the same direction. Magnetized materials have their domains arranged in the same direction. Magnetic domains are groups of atoms that have their magnetic fields aligned. Magnetic domains are groups of atoms that have their magnetic fields aligned. Magnetized materials have their domains arranged in the same direction. Magnetized materials have their domains arranged in the same direction.

10. Ferromagnetic Materials Ferro comes from ferrum which means iron in Latin. Ferro comes from ferrum which means iron in Latin. Ferromagnetic materials are materials that show strong magnetic properties. Ferromagnetic materials are materials that show strong magnetic properties. Examples: iron, nickel, cobalt, gadolinium, samarium, neodymium Examples: iron, nickel, cobalt, gadolinium, samarium, neodymium Ferro comes from ferrum which means iron in Latin. Ferro comes from ferrum which means iron in Latin. Ferromagnetic materials are materials that show strong magnetic properties. Ferromagnetic materials are materials that show strong magnetic properties. Examples: iron, nickel, cobalt, gadolinium, samarium, neodymium Examples: iron, nickel, cobalt, gadolinium, samarium, neodymium

11. Making, Changing, and Destroying Magnets Permanent magnets are made from materials that keep their magnetism. Permanent magnets are made from materials that keep their magnetism. Temporary magnets are made from materials the easily lose their magnetism. Temporary magnets are made from materials the easily lose their magnetism. Heating a magnet, stroking a magnet back and forth with another magnet, and striking/dropping a magnet can destroy its magnetism. Heating a magnet, stroking a magnet back and forth with another magnet, and striking/dropping a magnet can destroy its magnetism. Permanent magnets are made from materials that keep their magnetism. Permanent magnets are made from materials that keep their magnetism. Temporary magnets are made from materials the easily lose their magnetism. Temporary magnets are made from materials the easily lose their magnetism. Heating a magnet, stroking a magnet back and forth with another magnet, and striking/dropping a magnet can destroy its magnetism. Heating a magnet, stroking a magnet back and forth with another magnet, and striking/dropping a magnet can destroy its magnetism.

12. Breaking Magnets If a magnet is broken in two, you end up with two magnets each with a North and South pole. If a magnet is broken in two, you end up with two magnets each with a North and South pole.

13. Electromagnetism

14. Electric Current and Magnetism An electric current produces a magnetic field. An electric current produces a magnetic field. The relationship between electricity and magnetism is called electromagnetism. The relationship between electricity and magnetism is called electromagnetism. An electric current produces a magnetic field. An electric current produces a magnetic field. The relationship between electricity and magnetism is called electromagnetism. The relationship between electricity and magnetism is called electromagnetism.

15. Solenoids A solenoid is a coil of wire with a current. A solenoid is a coil of wire with a current. The more coils a solenoid has the stronger the magnetic field. The more coils a solenoid has the stronger the magnetic field. A solenoid is a coil of wire with a current. A solenoid is a coil of wire with a current. The more coils a solenoid has the stronger the magnetic field. The more coils a solenoid has the stronger the magnetic field.

16. Electromagnets An electromagnet is a solenoid with a ferromagnetic core. An electromagnet is a solenoid with a ferromagnetic core. This type of magnet can be turned on and off. This type of magnet can be turned on and off. An electromagnet is a solenoid with a ferromagnetic core. An electromagnet is a solenoid with a ferromagnetic core. This type of magnet can be turned on and off. This type of magnet can be turned on and off.

17. Increasing the Strength of an Electromagnet Use a stronger ferromagnetic core Use a stronger ferromagnetic core Add more coils to the solenoid Add more coils to the solenoid Wind the coils of the solenoid closer together Wind the coils of the solenoid closer together Increase the electrical current by adding more voltage. Increase the electrical current by adding more voltage. Use a stronger ferromagnetic core Use a stronger ferromagnetic core Add more coils to the solenoid Add more coils to the solenoid Wind the coils of the solenoid closer together Wind the coils of the solenoid closer together Increase the electrical current by adding more voltage. Increase the electrical current by adding more voltage.

18. Uses of Electromagnets Junkyard Cranes, Circuit Breakers, and Junkyard Cranes, Circuit Breakers, and MRI’s just to name a few. MRI’s just to name a few. Junkyard Cranes, Circuit Breakers, and Junkyard Cranes, Circuit Breakers, and MRI’s just to name a few. MRI’s just to name a few.