Home 2Home Chapter 2: Electricity for Everyone |
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| Chapter Challenge Homes For Everyone again establishes the scenario, this time with the need for electricity for all homes. Wind is given as the universally available source for generating electricity. Students are challenged to write a manual that describes how to obtain electricity from the generator. They then must determine which electrical appliances can and should be provided for use in all homes built by Homes For Everyone. Chapter Summary To gain understanding of the content necessary to meet this challenge, students collaborate on activities in which they learn about electromagnetic motors, how electricity is generated, the use of wind to generate electricity, and the relative efficiency of different appliances. These experiences engage students in the content identified in the National Science Education Standards. |
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Activity Summaries |
Physics Principles |
Activity One: Generate Students investigate electrical energy and electric circuits with a simple hand generator, wires, and bulbs. Using the hand generator introduces the concept that electricity is the result of converting one form of energy into another. |
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Activity Two: Lighten Up An experiment in which students compare the relative brightness of light bulbs in series and parallel circuits and increases their understanding of energy flow necessary in generating electricity. They also learn that a generator has a limit of what it can support. Students also read to learn more about electrical energy. |
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Activity Three: Load Limit To experience load limit, students add bulbs to their simple circuit until the load is exceeded. They then calculate the load limit of a household circuit and watts required by appliances, comparing these to the limits given in the challenge. This also introduces use of terms and equations for calculating power. |
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Activity Four: Who's In Control? Students again assemble a parallel circuit to explore how switches control the flow of electricity to specific bulbs. They then propose and test strategies for using parallel circuits and switches to increase the number of bulbs on a circuit. Finally, they are introduced to circuit diagrams. |
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Activity Five: Cold Shower Electricity used by water heaters is the focus of this activity, which also reinforces concepts of energy transfer. Students investigate the amount of energy in joules needed to raise the temperature of water, then calculate the efficiency of different water heaters. They also consider alternate solutions to the expectation for hot water in a home. |
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Activity Six: Pay Up Students compare different electric bills as they continue to explore concepts related to power consumption, efficiency of electrical appliances, and relative costs and benefits of specific electrical appliances. This activity also serves to review concept units used to communicate about energy transformation. |
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Activity Seven: More for Your Money Students conduct an experiment in which they determine and compare the power consumed and the efficiency of three systems that could be used to heat water. They apply data collected to confirm their response to the challenge in which they recommend appliances for the universal home. |
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