Young's modulus depends upon

Options

A. Stress applied on material
B. Strain produced in material
C. Temperature of material
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Young's Modulus**:
Young's modulus (E) is defined as the ratio of tensile stress (force per unit area) to tensile strain (proportional deformation in length). It is a measure of the stiffness of a solid material.

2. **Identifying Properties**:
Young's modulus is a material property, meaning it is intrinsic to the material itself. It does not depend on the amount of force applied or the extent of deformation.

3. **Factors Affecting Young's Modulus**:
- **Material Composition**: Different materials have different Young's moduli based on their atomic structure and bonding.
- **Temperature**: The Young's modulus can change with temperature. As the temperature increases, the material may become more ductile, which can lower its Young's modulus.
- **Pressure**: Changes in pressure can also affect the Young's modulus, particularly in gases and liquids.

4. **Conclusion**:
Therefore, Young's modulus primarily depends on the material's intrinsic properties and can be influenced by temperature and pressure. The most significant factors are the material composition and temperature.

### Final Answer:
Young's modulus depends on the material composition and can be influenced by temperature and pressure.

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