Electrical resistivity of a given metallic wire depends upon :

Options

A. its length
B. its thickness
C. its shape
D. nature of the material

Explanation

### Step-by-Step Solution:

1. **Understanding Electrical Resistivity**:
Electrical resistivity is a property of a material that quantifies how strongly it resists the flow of electric current. It is denoted by the symbol ρ (rho).

2. **Factors Affecting Resistivity**:
The resistivity of a metallic wire is influenced by several factors, primarily:
- The nature of the material (type of metal).
- The temperature of the material.

3. **Nature of the Material**:
Different materials have different numbers of free electrons available for conduction. For example, metals like copper and silver have high densities of free electrons, leading to lower resistivity, while materials like rubber have very few free electrons, leading to high resistivity.

4. **Temperature Dependence**:
As the temperature of a metallic wire increases, the resistivity generally increases. This is because higher temperatures cause the metal atoms to vibrate more, which can impede the flow of electrons.

5. **Conclusion**:
Therefore, the electrical resistivity of a given metallic wire depends on:
- The nature of the material (which determines the number of free electrons).
- The temperature of the conductor (which affects the movement of these electrons).

### Final Answer:
The electrical resistivity of a given metallic wire depends upon the nature of the material and the temperature.

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