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Questions
What is meant by coherent sources?
What are coherent sources?
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Solution
Two light sources are said to be coherent if they produce waves that have the same phase or constant phase difference, same frequency or wavelength (monochromatic), same waveform and preferably the same amplitude.
RELATED QUESTIONS
Write the important characteristic features by which the interference can be distinguished from the observed diffraction pattern.
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Answer the following question.
Describe any two characteristic features which distinguish between interference and diffraction phenomena. Derive the expression for the intensity at a point of the interference pattern in Young's double-slit experiment.
Answer in brief:
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`[sin 45^circ = cos 45^circ = 1/sqrt 2]`
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