Piezoelectricity
A piezoelectric buzzer.Copyright 2007 I, Gophi, Wikimedia Commons http://commons.wikimedia.org/wiki/File:2007-07-24_Piezoelectric_buzzer.jpg
Students learn about a fascinating electromechanical coupling called piezoelectricity that is being employed and researched around the world for varied purposes, often for creative energy harvesting methods. A PowerPoint® presentation provides an explanation of piezoelectric materials at the atomic scale, and how this phenomenon converts mechanical energy to electrical energy. A range of applications, both tested and conceptual, are presented to engage students in the topic. Gaining this background understanding prepares students to conduct the associated hands-on activity in which they create their own small piezoelectric "generators."
Engineers find electromechanical couplings intriguing and useful because of their ability to convert energy from mechanical to electrical, or vice versa. One example is piezoelectricity, a well-known electromechanical coupling since the early 20th century. The cause of this unique material property is explained by the arrangement of atoms in the material. Once engineers understand this, they are able to predict which materials have the potential for piezoelectric responses and how strong those responses might be, so as to incorporate the materials into creative, useful design solutions, from light-up shoes to sensors and actuators to energy harvesting systems.
After this lesson, students should be able to:
- Explain the piezoelectric effect and the converse piezoelectric effect.
- Describe how the atomic structure of a material determines if it is piezoelectric.
- List numerous applications for piezoelectric materials.