Can the potential barrier across a `p - n` junction be measured by simply connecting a voltmeter across the junction ?

Explanation

To determine whether the potential barrier across a p-n junction can be measured by simply connecting a voltmeter across the junction, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding the p-n Junction**:
- A p-n junction is formed by joining p-type and n-type semiconductors. The p-type semiconductor has an abundance of holes (positive charge carriers), while the n-type has an abundance of electrons (negative charge carriers).

**Hint**: Remember that the p-n junction consists of two different types of semiconductors with distinct charge carriers.
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