What do you understand by coherent sources ?

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Coherent Sources:**
Coherent sources are defined as two or more wave sources that produce waves with specific characteristics.

2. **Same Frequency:**
For sources to be coherent, they must emit waves that have the same frequency. This means that the number of wave cycles produced per unit time is identical for both sources.

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