The behavior of a 555 integrated circuit is an excellent way to illustrate the following:

  • A review of the basic relationships for resistors connected in series and in parallel

  • A review of the basic relationships for capacitors connected in series and in parallel

  • Engineering application of basic physics knowledge1 

  • Engineering design concepts such as limited resources, data analysis, maximizing performance, and minimizing cost

This activity is appropriate for students in advanced high school or college introductory physics and is based on the idea that students learn more effectively when they are engaged in investigations, discussions, model building, problem solving, and other active explorations. The instructor might engage the students by showing them a completed 555 timing circuit and letting the class discuss what components are used in the circuit, and how they think these components might affect the flashing rate. Then the instructor can challenge thestudents to build the...

Supplementary Material

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