Question

Write a short note on pyroelectricity.

Answer 1

Pyroelectricity is the ability of certain crystals to generate an electric charge when they are heated or cooled. This phenomenon happens because temperature changes cause a shift in the positions of atoms in the crystal, leading to a change in polarization and the development of surface charges. The effect is temporary and depends on the rate of temperature change. Common pyroelectric materials include tourmaline and lithium niobate. Pyroelectricity is used in infrared sensors, motion detectors, and thermal imaging devices.