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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 necessary conditions to obtain sustained interference fringes.
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(i) \[y = a_1 \sin \omega t\]
(ii) \[y = a_2 \sin \left( \omega t + \epsilon \right)\]
(iii) \[y = a_1 \sin 2\omega t\]
(iv) \[y = a_2 \sin 2\left( \omega t + \epsilon \right).\]
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(b) (i) and (iii)
(c) (ii) and (iv)
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