We can use a rheostat as a potential divider.

Explanation

To solve the question of how a rheostat can be used as a potential divider, we can break it down into several steps:

### Step-by-Step Solution:

1. **Understanding the Rheostat**:
- A rheostat is a variable resistor used to control current in a circuit. It has three terminals: two fixed terminals and one sliding contact (wiper) that can move along a resistive element.

2. **Setting Up the Circuit**:
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