Hook's law defines

Options

A. stress
B. strain
C. modulus of elasticity
D. elastic limit

Answer

**Step-by-Step Solution:**

1. **Understanding Hook's Law**: Hook's Law states that the strain in a solid is proportional to the applied stress within the elastic limit of that material. This means that if you stretch or compress a material, it will deform in proportion to the force applied, as long as the material is not permanently deformed.

2. **Defining Key Terms**:
- **Stress**: This is defined as the force applied per unit area of a material. It is usually measured in Pascals (Pa).
- **Strain**: This refers to the deformation of the material in response to stress. It is a dimensionless quantity, representing the change in length divided by the original length.

3. **Elastic Limit**: The elastic limit is the maximum amount of stress that a material can withstand without undergoing permanent deformation. Beyond this limit, the material will not return to its original shape once the stress is removed.

4. **Conclusion**: Therefore, Hook's Law defines the relationship between stress and strain within the elastic limit of a material, indicating that stress is directly proportional to strain.

5. **Final Answer**: Hook's Law defines the limit of elasticity where stress is directly proportional to strain.

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