Which principle states that materials produce a voltage when deformed by applied pressure?

Which principle states that materials produce a voltage when deformed by applied pressure?

• A. Piezoelectric
• B. Magnetostrictive
• C. Photoconductive
• D. Pyroelectric

Answer: (A)

The principle described is the piezoelectric effect: certain materials generate an electric voltage when they are physically deformed by applied pressure. When mechanical stress is applied to these crystals, the internal lattice shifts and separates positive and negative charges, producing a measurable voltage. This effect is fundamental to ultrasound transducers, where piezoelectric crystals convert electrical energy into sound waves and then reconvert returning echoes into electrical signals. In contrast, magnetostrictive materials respond to magnetic fields by changing shape rather than generating voltage from pressure; photoconductive materials change conductivity in response to light rather than mechanical stress; and pyroelectric materials produce charge due to temperature change rather than pressure.

The principle described is the piezoelectric effect: certain materials generate an electric voltage when they are physically deformed by applied pressure. When mechanical stress is applied to these crystals, the internal lattice shifts and separates positive and negative charges, producing a measurable voltage. This effect is fundamental to ultrasound transducers, where piezoelectric crystals convert electrical energy into sound waves and then reconvert returning echoes into electrical signals. In contrast, magnetostrictive materials respond to magnetic fields by changing shape rather than generating voltage from pressure; photoconductive materials change conductivity in response to light rather than mechanical stress; and pyroelectric materials produce charge due to temperature change rather than pressure.