MCQ
Two identical lights sources $S_1$​ and $S_2$ emit the light of same wavelength $\lambda$. These light rays will exhibit interference if:
  • Their phase difference remain constant.
  • B
    Their phase difference is distributed randomly.
  • C
    Their light intensities remain constant.
  • D
    Their light intensities change continuously.

Answer

Correct option: A.
Their phase difference remain constant.

For interference to take place the light sources need to be either in phase or have a constant phase difference. In case the phase difference keeps changing the interference pattern will keep on changing, as a result of interference pattern will be observed.

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