A plane monochromatic light falls normally on a diaphragm with two narrow slits separated by a distance d = 2.5 mm. A fringe pattern is formed on the screen placed at D = 100 cm behind the diaphragm. If one of the slits is covered by a glass plate of thickness 10 m, then the distance by which these fringes will be shifted will be:
Correct answer: C. 4 mm
- A. 2 mm
- B. 3 mm
- C. 4 mm
- D. 5 mm
Explanation
When one of the slits is covered by a glass plate, the path length for light passing through the glass plate changes, leading to a shift in fringes. The correct shift in this scenario is 4 mm. Option A, B, and D are incorrect as they do not accurately calculate the shift based on the experimental setup and conditions.
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Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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