Lesson Summary In this lesson, students explore ways to use the motor as a generator of electricity.  They use the generator to operate a motor and light a bulb.  They also think about different ways to turn a generator and methods for generating larger amounts of electricity. Teacher Background There is a remarkable symmetry between electricity and magnetism.  We saw in Lesson 7, when the compass needle was moved by the electric current in the wire, that electric current has a magnetic field associated with it.  The fascinating “other hand” is that, when a wire is moved through a magnetic field, it causes an electric current to flow in the wire.  This was first realized in 1830.  It made possible the production of large quantities of inexpensive electricity and changed the world dramatically. The electricity that is generated by electric power companies is produced by the turning of enormous generators.  Most commonly, steam is produced by the burning of gas or coal or by a nuclear chain reaction; the steam is then directed through a turbine.  The steam makes the turbine rotate and the turbine turns the armature of a generator.  A hydroelectric plant uses the weight of falling water to power a turbine and a generator. In this lesson, when the students turn the shafts of their motors, an electric current is generated in the wires of the electromagnet on the armature.  The magnetism “pushes” the electricity, in a sense, along the wire.  However, an electric current is created only if the electricity has a circuit to flow through.  If the wires are not connected in a circuit, no electricity will flow. By connecting a lightbulb or another motor as part of the circuit, students can see the usefulness of the electricity they generate. Set-up/Management Tips You will need to have the motors put back together and working for this lesson. All materials can be handed out using the numbered baggies. Make sure that you have the class discussion before handing out materials. It is important to make sure students have an idea of the difference between a motor and a generator (one produces motion and one produces electricity). The rubber bands can quickly become damaged. Long, slow, soft strokes with the rubber bands work much better than short, quick, hard strokes. If you have not taught this lesson before, you may want to take some extra time to prepare your presentation of the concept of the generation of electricity in Steps 1 and 2 of the Procedure section.  This idea is astonishing for many students. Literacy Support Have students write in their science notebooks different ways they can think of to turn a generator. Have students draw a picture of the best method and write an explanation of why that method is best. Use the attachment called “Final Quiz” to assess students.  See the Student Activity Book for Lesson 16. Scientific Vocabulary The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit: No new vocabulary introduced this lesson.