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The piezoelectric effect and its inverse are also proportional. The voltage generated by the piezoelectric effect is proportional to: A) the amount of force applied, and; B) the type of force applied (i.e. tension and compression produce opposite polarities). Likewise, the mechanical response of the inverse piezoelectric effect is proportional to: A) the field's strength, and; B) the field’s polarity.
The piezoelectric effect is passive, and requires no additional power other than the mechanical or electric stimulus.
Applications (Aleksi)
http://www.youtube.com/watch?v=fHp95e-CwWQ
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