The product of resistivity and conductivity of a cylindrical conductor depends on

Options

A. (a) temperature
B. (b) meterial
C. (c ) area of cross cestion
D. (d) none of these

Answer

To solve the question regarding the product of resistivity and conductivity of a cylindrical conductor, we can follow these steps:

### Step 1: Understand the Definitions
1. **Resistivity (ρ)**: This is a material property that quantifies how strongly a given material opposes the flow of electric current. It is measured in ohm-meters (Ω·m).
2. **Conductivity (σ)**: This is the reciprocal of resistivity and measures how easily electricity flows through a material. It is measured in siemens per meter (S/m).

### Step 2: Relate Resistivity and Conductivity
The relationship between resistivity and conductivity is given by the formula:
\[ \rho = \frac{1}{\sigma} \]
This implies that:
\[ \rho \cdot \sigma = 1 \]
This indicates that the product of resistivity and conductivity is a constant value.

### Step 3: Analyze the Dependencies
Since we have established that:
\[ \rho \cdot \sigma = 1 \]
This product does not depend on any external factors such as temperature, material, or area of cross-section. It is a fundamental relationship that holds true for any material.

### Step 4: Conclusion
Thus, the product of resistivity and conductivity of a cylindrical conductor is independent of temperature, material, area of cross-section, or any other variable. Therefore, the correct answer is:
**None of these (Option D)**.

### Final Answer
The product of resistivity and conductivity of a cylindrical conductor does not depend on anything (Option D).

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