NEET PhysicsClass 12Coherent and incoherent additionEasyAssertion–Reason

Two separate sodium lamps of equal brightness illuminate the same region of a screen. Read the Assertion (A) and Reason (R) and choose the correct option.

Assertion (A): No steady interference fringes are seen on the screen.
Reason (R): The phase of light from each independent source changes randomly in times of about 10⁻¹⁰ s, so there is no constant phase difference between the two.

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Two separate sodium lamps of equal brightness illuminate the same region of a screen. Read the Assertion (A) and Reason (R) and choose the correct option.

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