MCQ
The light source will be coherent if :
  • The phase difference remains fixed at their place of origin
  • B
    They should have the same amplitude
  • C
    Their frequency should be same
  • D
    All the above mentioned things are present.

Answer

Correct option: A.
The phase difference remains fixed at their place of origin
(A) - The phase difference remains fixed at their place of origin

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