The ratio of hydraulic stress to the corresponding strain is known as

Options

A. Young's modulus
B. compressibility
C. rigidity modulus
D. Bulk modulus

Explanation

To solve the question, we need to understand the relationship between hydraulic stress, strain, and the term that describes their ratio.

### Step-by-step Solution:

1. **Understand Hydraulic Stress**:
Hydraulic stress is the pressure applied to a fluid. It is defined as the force per unit area exerted by the fluid.

2. **Understand Strain**:
Strain is a measure of deformation representing the displacement between particles in a material body. In the context of fluids, it can be understood as the relative change in volume.

3. **Define the Ratio**:
The question asks for the ratio of hydraulic stress to the corresponding strain. Mathematically, this can be expressed as:
\[ \text{Ratio} = \frac{\text{Hydraulic Stress}}{\text{Strain}} \]

4. **Identify the Term**:
In physics, particularly in the study of elasticity, the ratio of stress to strain is known as a modulus. For fluids, this specific ratio is referred to as the **bulk modulus**.

5. **Conclusion**:
Therefore, the ratio of hydraulic stress to the corresponding strain is known as the **bulk modulus**.

### Final Answer:
The ratio of hydraulic stress to the corresponding strain is known as **bulk modulus**.

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