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Some crystals, such as quartz, produce an electric charge when squeezed. This is the piezoelectric effect, discovered in 1880 by the brothers Pierre and Jacques Curie, years before Pierre's research on radioactivity with Marie Curie. It makes the spark when you press the button of a gas lighter.

Pierre Curie & Jacques Curie, 1880

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The story behind the card

'Piezo' comes from the Greek word for 'press'. The effect also works in reverse, as the physicist Gabriel Lippmann predicted in 1881 and the Curies soon confirmed: an electric voltage makes the crystal change shape very slightly. That reverse effect keeps time in quartz watches, where a tiny quartz crystal vibrates 32,768 times a second, and it produces and detects the sound pulses of sonar and medical ultrasound. Pierre married Marie Skłodowska in 1895; together they discovered polonium and radium and shared the 1903 Nobel Prize in Physics with Henri Becquerel. Jacques became a professor of mineralogy at Montpellier.

Türkçe oku
Kuvars gibi bazı kristaller sıkıştırılınca elektrik yükü üretir. Piezoelektrik etki denen bu olayı 1880'de Pierre ve Jacques Curie kardeşler keşfetti; Pierre'in Marie Curie ile radyoaktivite araştırmalarından yıllar önce. Bir gaz çakmağının düğmesine bastığınızda çıkan kıvılcım da bu etkiden gelir.

“Piezo” sözcüğü Yunanca “bastırmak” anlamındaki fiilden gelir. Etki tersine de işler: Fizikçi Gabriel Lippmann 1881'de bunu öngördü, Curie kardeşler de kısa süre sonra doğruladı. Kristale elektrik gerilimi uygulanınca kristalin biçimi çok az değişir. Bu ters etki kuvars saatlerde zamanı tutar; saatin içindeki minik kuvars kristali saniyede 32.768 kez titreşir. Sonarda ve tıpta kullanılan ultrasonda ses atımlarını üreten ve algılayan da aynı etkidir. Pierre 1895'te Marie Skłodowska ile evlendi; ikisi polonyum ve radyum elementlerini keşfetti ve 1903 Nobel Fizik Ödülü'nü Henri Becquerel ile paylaştı. Jacques ise Montpellier'de mineraloji profesörü oldu.

Sources and further reading

Background reading: Piezoelectricity
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