In a two-slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by 5 x 10^-2m towards the slits, the change in fringe width is 3 x 10^-5 m. If the separation between the slits is 10-3 m, the wavelength of light used is:
Correct answer: A. 6000 Å
- A. 6000 Å
- B. 5000 Å
- C. 3000 Å
- D. 4500 Å
Explanation
By using the formula for fringe width in a two-slit experiment, the wavelength of light is calculated as 6000 Å. When the screen is moved by 5x10-2m towards the slits, the change in fringe width is 3x10-5m. Given the separation between the slits as 10-3m, the correct answer is 6000 Å.
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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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