Piezoelectricity - why hitting crystals makes electricity

Heya, Steve. Good to see you back again.

The part of this video that I think I most appreciate is the actual look at the guts of a piezo electric safety lighter. I've used them for a long time and never quite been sure how they work on the inside.

I also appreciate Steve's comments on quarts 'healing crystals' around 1:40. "Don't know if you take it orally or..."

And then we get into the fact that piezoelectricity is dependent on the electronegativity differences in a quart crystal (admittedly simplified in Steve's peanut-butter-jar model). I'm totally duplicating this post for my chem blog because of that explanation.

Smart Materials of the Future - with Anna Ploszajski

"Rock-paper-scissors is a game that you use to compare materials' properties. The rock blunts the scissors because rock is harder than stainless steel."

C'mon, nerd, rock-paper-scissors is just a game like mumbledepeg or roshambo.

The simplicity of showing a smart material via pine cones is brilliant.

Oh, I found a definition of smart materials that I very much like (via BBC): "[s]mart materials have properties that react to changes in their environment. This means that one of their properties can be changed by an external condition, such as temperature, light, pressure or electricity. This change is reversible and can be repeated many times."

Other smart materials mentioned in the video are lime mortar from the Egyptian pyramids, piezoelectric quartz crystals, thermochromic pigments (on a mug), NiTiNOL, and ferrofluids. Most of the latter materials are applied to the future of airplane design.

Piezoelectricity round-up

Clearly piezoelectricity is way more common than I knew.

Sugar crystals? DNA? Bones? All are piezoelectric?

And if piezoelectric crystals lack a center of symmetry (2:20), how the heck is quartz piezoelectric? It looks awfully symmetrical to me.

Apparently, though, the quartz crystal is absolutely piezoelectric, as shown by Bill Hammack, the Engineer Guy...



Theoretically, it's possible to make and test your own piezoelectric crystal at home...(though sadly he uses a commercial piezoelectric crystal to make his guitar pickup)



As to how we can make use to piezoelectrcitiy...

• Top uses of piezoelectricity in everyday applications (inkjet printers, earbuds, tennis racquets, course-changing bullets, humidifiers, sonar, pressure sensors)
• Applications of piezoelectricity (from wikipedia)
• Piezoelectricity and its uses (even explaining how some tennis racquets use piezoelectrcity)