When one of the slits of Young's experiment is covered with a transparent sheet of thickness 4.8 mm, the central fringe shifts to a position originally occupied by the 30th bright fringe. What should be the thickness of the sheet if the central fringe has to shift to the position occupied by the 20th bright fringe?
Correct answer: D. 3.2 mm
- A. 3.8 mm
- B. 1.6 mm
- C. 7.6 mm
- D. 3.2 mm
Explanation
When one of the slits is covered with a sheet of thickness 4.8 mm, the central fringe shifts to the position of the 30th bright fringe. To shift it to the 20th bright fringe, the sheet thickness needs to be reduced. The correct thickness of the sheet to achieve this shift is 3.2 mm. The other options do not align with the required shift in the central fringe position.
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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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