Definition
A physical phenomenon in which certain crystals, such as quartz, tourmaline, and Rochelle salt, produce a small electrical voltage across their surfaces when mechanically squeezed, bent, or struck. The same crystals also work in reverse: applying a voltage to them causes them to flex or vibrate.
Plain English
Some crystals make electricity when you press on them, and they bend or vibrate when you put electricity through them.
Context Anchor
Seen in aircraft electrical, instrument, and maintenance discussions, especially around sensors that turn pressure or vibration into an electrical signal.
Derivation
From the Greek piezein, meaning 'to press' or 'to squeeze,' combined with 'electric.' Literally, 'pressure-electricity' — which captures exactly what the effect does.
Why Pilots Care
Several aircraft components rely on this effect, including some pressure sensors, accelerometers, and certain types of igniters. Knowing the principle helps you understand how a tiny crystal can generate a usable signal with no battery or external power.
Grounding Statement
Picture a tiny sensor being squeezed by changing pressure and responding by sending out a small electrical signal.
Intuition Check
This is not electricity made by rubbing something, like static electricity. It is electricity made when certain materials are physically pressed, bent, or vibrated.
Example Sentence 1
The pressure sensor uses the piezoelectric effect to convert cabin pressure changes into a small electrical signal the instrument can read.
Example Sentence 2
Vibration monitors in turbine engines detect abnormal frequencies through sensors that operate on the piezoelectric effect.