The figure shows a double-slit experiment. P and Q are the slits. The path lengths PX and QX are nλ and (n+2)λ respectively, where n is a whole number and λ is the wavelength. Taking the central fringe as zero, what is formed at X:
Correct answer: C. Second bright
- A. First bright
- B. First dark
- C. Second bright
- D. Second dark
Explanation
In this scenario, the path lengths PX and QX differ by a path difference of 2λ. This corresponds to constructive interference, resulting in the formation of the second bright fringe at X. The other options are incorrect because they do not align with the path difference of the given scenario.
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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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