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Wave Optics — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsWave Optics1 Mark
Question

In a Young's double  slit experiment the source S and the two slits A and B are vertical with slit A above slit B. The fringes are observed on a vertical screen K. The optical path length from S to B is increased very slightly (by introducing a transparent material of higher refractive index) and the optical path length from S to A is not changed, as a result the fringe system on K moves

(a) Vertically downwards slightly

(b) Vertically upwards slightly

(c) Horizontally, slightly to the left

(d) Horizontally, slightly to the right
✓

Answer

(a) Vertically downwards slightly

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