The substance which possesses zero resistance at zero K temperature is called a:

Options

A. Conductor
B. Super conductor
C. Insulator
D. Semiconductor

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of Resistance:**
- Resistance is a measure of the opposition to the flow of electric current in a material. Different materials exhibit different levels of resistance.

2. **Identifying Types of Materials:**
- There are three main categories of materials based on their electrical properties:
- **Conductors:** Materials that allow electricity to flow easily (e.g., metals).
- **Insulators:** Materials that do not allow electricity to flow (e.g., rubber, glass).
- **Semiconductors:** Materials that can act as either conductors or insulators depending on conditions (e.g., silicon).

3. **Defining Superconductors:**
- A superconductor is a special type of material that exhibits zero electrical resistance when cooled below a certain critical temperature (denoted as zero Kelvin or absolute zero). This means that it can conduct electricity without any energy loss.

4. **Conclusion:**
- Based on the definition provided, the substance which possesses zero resistance at zero Kelvin temperature is called a **superconductor**.

**Final Answer:**
The substance which possesses zero resistance at zero K temperature is called a **superconductor**.

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