Certain crystals produce electric signals on application of pressure .This phenomenon is called

Options

A. Pyroelectricity
B. Ferroelectricity
C. Piezoelectricity
D. Ferrielectricity

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a phenomenon where certain crystals generate electric signals when pressure is applied to them.

2. **Identifying the Phenomenon**: The phenomenon described is related to the behavior of certain materials under mechanical stress. When these materials are subjected to pressure, they produce an electric charge.

3. **Defining the Term**: The specific term for this phenomenon is "piezoelectricity." The word "piezo" comes from the Greek word for pressure, and "electricity" refers to the electric signals generated.

4. **Explaining Piezoelectricity**: Piezoelectricity is the ability of certain crystals to generate an electric voltage when they are mechanically deformed. This means that when these crystals are squeezed or stressed, they produce an electrical signal.

5. **Reverse Effect**: Conversely, when an electric field is applied to a piezoelectric material, it can cause mechanical deformation, such as shrinking or expanding. This is known as the reverse piezoelectric effect.

6. **Conclusion**: Therefore, the correct answer to the question is that the phenomenon where certain crystals produce electric signals on application of pressure is called "piezoelectricity."

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