Draw a labelled circuit diagram of a potentiometer to compare emfs of two cells. Write the working formula (Derivation not required).

Explanation

### Step-by-Step Solution

**Step 1: Draw the Circuit Diagram**
To compare the EMFs of two cells using a potentiometer, we first need to draw a labeled circuit diagram. The diagram consists of the following components:

1. **Potentiometer Wire**: A long wire that provides a uniform potential gradient.
2. **Two Cells (E1 and E2)**: The two cells whose EMFs we want to compare.
3. **Key (K)**: A switch to connect or disconnect the circuit.
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