Electricity and Magnetism Magic of Electrons © 2011 Project Lead The Way, Inc.

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Electricity and Magnetism What is a Magnet? North and South Poles of a Magnet Types of Magnets The Earth as a Magnet Electromagnets Electromagnetic Induction Motors Generators

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? What is a Magnet? An object that is surrounded by a magnetic field and has the property of attracting iron or steel

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Where are Magnets? Magnets. . . Generate electricity Image courtesy of DOE/NREL Image courtesy of DOE/NREL Are in motors Generate electricity: Turbines are turned at power plants by heated steam, water pressure, etc., to spin a turbine surrounded by magnets to generate electricity. Students will make a generator in an upcoming activity. Motors spin because of the magnetic field that is created from electricity. Students will create a motor in an upcoming activity.

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Where are Magnets? Magnets. . . Power car windows & locks Image courtesy of NASA Are used in Magnetic Resonance Imaging (MRI) Power windows use a small motor, and power door locks use a solenoid. The clicking noise heard when the mechanisms lock or unlock is the release and activation of an electromagnet. Students will create an electromagnet in an upcoming activity.

North and South Poles of a Magnet Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? North and South Poles of a Magnet Magnets have a north and south pole. If a magnet is broken into smaller pieces, each piece will still have a north and south pole. Opposite poles attract, like poles repel. N S N S S N N S N S N S N S N S N S

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Types of Magnets Magnets in Nature Magnetite is a mineral that is naturally magnetic. Human-Made Magnets Some materials can be magnetized when placed near a strong magnetic field. Soft magnetic materials (Iron) Hard magnetic materials (Cobalt, Nickel) Electromagnets Magnets can be made by passing a current through a coil of wire. U.S. Geological Survey / photo by Andrew Silver Magnetite was created by proximity to the Earth’s magnetic field. Most magnets are made using current, vibration, and heat. Soft magnetic materials are easily magnetized, but also lose magnetism easily. Hard magnetic materials are difficult to magnetize, but tend to stay magnetized. Almost all magnetic materials are alloys, which are combinations of different elements. These alloys contain naturally magnetic elements.

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? The Earth as a Magnet The Earth is a large magnet. North Pole South Pole Compasses work as a result of the Earth’s magnetic field.

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Electromagnets Magnets are created by passing a current through a wire. Electromagnets are generally wire wrapped around an iron core. Electromagnets are turned on and off when the current is switched on and off.

Electricity and Magnetism PLTW Gateway® Unit 4 – Lesson 4.1 – What is Electricity? Image Resources Microsoft, Inc. (2008). Clip Art. Retrieved October 20, 2008, from http://office.microsoft.com/en-us/clipart/default.aspx U.S. Geological Survey Photographic Library (USGS). (2006). Retrieved October 20, 2008, from http://libraryphoto.cr.usgs.gov/index.html National Renewable Energy Laboratory (2008). Photographic information eXchange. Retrieved October 21, 2008, from http://www.nrel.gov/data/pix/searchpix.html