Potentiometer wire is made of manganin because it has

Options

A. If both Assertion `&` Reason are True `&` the Reason is a correct explanantion of the Assertion
B. If both Assertion `&` Reason True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason is False
D. If both Assertion `&` Reason are False.

Answer

**Step-by-Step Solution:**

1. **Understanding the Potentiometer:**
A potentiometer is an instrument used to measure the potential difference (voltage) across two points in a circuit. It consists of a long wire of uniform cross-section and material.

2. **Material Selection for Potentiometer Wire:**
The wire used in a potentiometer must have specific properties to ensure accurate measurements. One of the key properties is the stability of resistance with temperature changes.

3. **Why Manganin?**
Manganin is a copper-manganese alloy that is commonly used for potentiometer wires. The primary reason for using manganin is its low temperature coefficient of resistance.

4. **Temperature Coefficient of Resistance:**
The temperature coefficient of resistance is a measure of how much the resistance of a material changes with temperature. A low temperature coefficient means that the resistance remains relatively constant even when the temperature changes.

5. **Advantages of Low Temperature Coefficient:**
- **Stable Resistance:** Manganin maintains a stable resistance over a wide range of temperatures, which is crucial for accurate voltage measurements.
- **Minimized Errors:** Since the resistance does not change significantly with temperature, it minimizes errors in measurements that could arise from temperature fluctuations.

6. **Conclusion:**
Therefore, the potentiometer wire is made of manganin because it has a low temperature coefficient of resistance, ensuring that the resistance remains constant even with changes in temperature, leading to more accurate and reliable measurements.

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