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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.
Four light waves are represented by
(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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(a) (i) and (ii)
(b) (i) and (iii)
(c) (ii) and (iv)
(d) (iii) and (iv)
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Answer in brief:
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`[cos pi/2=0]`
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