MCQ
Coherent sources are those sources for which
  • A
    Phase difference remain constant
  • B
    Frequency remains constant
  • Both phase difference and frequency remains constant
  • D
    None of these

Answer

Correct option: C.
Both phase difference and frequency remains constant
c
A coherent source continuously emits light with a constant frequency and wavelength. Also, the phase difference in the light waves are always constant. If these properties are satisfied, only then a source is called coherent.

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