Conductivity of a conductor depends upon

Options

A. length
B. volume
C. area of cross-section
D. temperature

Explanation

### Step-by-Step Solution

1. **Understanding Conductivity**:
- Conductivity is the ability of a material to conduct electric current. It is denoted by the symbol σ (sigma) and is the reciprocal of resistivity (ρ).
- The formula relating conductivity and resistivity is given by:
\[ \sigma = \frac{1}{\rho} \]

2. **Factors Affecting Conductivity**:
- The conductivity of a conductor can depend on several factors, including:
- Length of the conductor
- Area of cross-section
- Volume of the conductor
- Temperature of the conductor

3. **Analyzing Each Factor**:
- **Length**:
- Increasing the length of a conductor does not increase its conductivity. In fact, longer conductors typically have higher resistance, which would lower conductivity.
- **Area of Cross-Section**:
- While a larger cross-sectional area can allow more current to pass through, it does not inherently increase the conductivity of the material itself. Conductivity is more about the material's properties than its dimensions.
- **Volume**:
- The volume of the conductor does not directly affect its conductivity. Conductivity is a property of the material, not its size.
- **Temperature**:
- The effect of temperature on conductivity is significant. For metals, as temperature increases, the vibrations of metal ions increase, which can lead to increased resistance and thus decreased conductivity. However, for electrolytic conductors, increased temperature can lead to increased ionization, which increases conductivity.

4. **Conclusion**:
- From the analysis, we can conclude that the conductivity of a conductor primarily depends on temperature. In metals, higher temperatures lead to decreased conductivity due to increased resistance, while in electrolytic conductors, higher temperatures can lead to increased conductivity due to increased ionization.

### Final Answer:
**Conductivity of a conductor depends primarily on temperature.**

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