Making an electric current with magnets Or, The lights are on, even when nobody’s home!

Stuff you’ll be expected to know when we’re done here….

Wire coils and magnets ---- Remember that a wire coil with electricity flowing through it has a magnetic field. If there is a magnetic inside the coil, movement of the magnet will produce an electric current in the wire The direction of the magnet’s movement affects the direction of the current

Relative motion - Generating a current can be done by either moving the magnet or moving the wire. As long as there is relative motion, a current will be generated. Because the current changes direction in a regular pattern as the magnet moves, this is called alternating current, or AC

Direct current Batteries provide electricity that flows in only one direction – called direct current or DC. A commutator on a coil-and-magnet generator can also change the AC current to DC. Thomas Edison advocated for AC current, Nicolai Tesla advocated for DC. If Tesla had won the argument, electricity today would be free for everyone, and the DWP would just be the DW.

Generators in our power plants Generators convert the mechanical energy of movement into electrical energy. In the diagram to the right, The mechanical energy is provided by the wind

Mechanical energy sources Steam is the most common source of mechanical energy in the power plants across the US today. The heat to create the steam can come from a variety of sources: Burning coal Burning natural gas Burning petroleum Nuclear energy Focused sunlight Some of these are cleaner and more renewable than others.

transformers

Where are the transformers?

What’s the assignment? Glad you asked…. Read pages 734 - 740 Complete “math Skills” worksheet. Page 53 from online resources. If you need help, check out the right margin on page 739 of the text.