Interference fringes from sodium light (1 = 5890 Å) in a double slit experiment have an angular width of 0.20o. To increase the fringe width by 10%, the wavelength of light used should be:
Correct answer: D. 6479 Å
- A. 5892 Å
- B. 4000 Å
- C. 8000 Å
- D. 6479 Å
Explanation
In interference patterns, the fringe width is directly proportional to the wavelength of light used. To increase the fringe width by 10%, a shorter wavelength of light should be used. The correct answer is 6479 Å, which is shorter than the original 5890 Å wavelength of sodium light used in the experiment. The other options do not take into account this relationship and are therefore incorrect.
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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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