Which term best describes the property that enables a material to generate a voltage when mechanically strained?

Which term best describes the property that enables a material to generate a voltage when mechanically strained?

• A. Ferroelectric property
• B. Elastic property
• C. Thermoelectric effect
• D. Piezoelectric effect

Answer: (D)

The key idea is the direct coupling between mechanical deformation and electrical voltage. In certain crystals that lack a center of symmetry, pressing or twisting the material shifts charged ions in a way that creates a net dipole moment, causing charges to accumulate and produce a voltage. This is the piezoelectric effect, and it’s the defining phenomenon when mechanical strain generates electrical signals. Many devices use it, from quartz watches to pressure sensors, and the effect can go in reverse—an applied electric field can make the material deform. Elastic properties describe how a material deforms under load, not how it generates voltage. Thermoelectric effects produce voltage from a temperature difference, not from mechanical strain. Ferroelectric properties involve spontaneous polarization that can be reversed by an electric field; while ferroelectric materials can be piezoelectric, the situation here is specifically about voltage generation from strain, which points to the piezoelectric effect.

The key idea is the direct coupling between mechanical deformation and electrical voltage. In certain crystals that lack a center of symmetry, pressing or twisting the material shifts charged ions in a way that creates a net dipole moment, causing charges to accumulate and produce a voltage. This is the piezoelectric effect, and it’s the defining phenomenon when mechanical strain generates electrical signals. Many devices use it, from quartz watches to pressure sensors, and the effect can go in reverse—an applied electric field can make the material deform.

Elastic properties describe how a material deforms under load, not how it generates voltage. Thermoelectric effects produce voltage from a temperature difference, not from mechanical strain. Ferroelectric properties involve spontaneous polarization that can be reversed by an electric field; while ferroelectric materials can be piezoelectric, the situation here is specifically about voltage generation from strain, which points to the piezoelectric effect.