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 1: Understanding the p-n Junction
A p-n junction is formed by joining p-type and n-type semiconductors. At the junction, electrons from the n-side and holes from the p-side recombine, creating a depletion region that has a built-in electric field and a potential barrier.

### Step 2: Concept of Potential Barrier
The potential barrier is the energy barrier that must be overcome for charge carriers (electrons and holes) to move across the junction. This barrier prevents the free flow of charge carriers under equilibrium conditions.

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