When is the series combination of cells advantageous and why?

Explanation

### Step-by-Step Solution:

1. **Understanding Series Combination of Cells**:
- A series combination of cells involves connecting multiple cells end-to-end, so that the positive terminal of one cell is connected to the negative terminal of the next cell.

2. **When is it Advantageous?**:
- The series combination of cells is advantageous when a **high potential difference** (or high electromotive force, EMF) is required for a circuit.

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