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Question
How do source and images behave as coherent sources?
Solution
- In the source and images method, a source and its image will act as a set of coherent sources, because the source and its image will have waves in-phase or constant phase difference as shown in the following figure.
- The Instrument, Fresnel’s biprism uses two virtual sources as two coherent sources and the instrument, Lloyd’s mirror uses a source and its virtual image as two coherent sources.
Using virtual and real images of a source as coherent sources
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