Why do we prefer potentiometer with a longer bridge wire?

Explanation

### Step-by-Step Solution:

1. **Understanding Potentiometer Basics**: A potentiometer is an instrument used to measure the potential difference (voltage) across two points in a circuit. It operates on the principle of balancing the potential difference with a known voltage.

2. **Potential Gradient Concept**: The potential gradient (k) is defined as the potential difference per unit length of the wire. It is given by the formula:
\[ k = \frac{V}{L} \]
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