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Question
Write three characteristic features to distinguish between the interference fringes in Young's double slit experiment and the diffraction pattern obtained due to a narrow single slit.
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Solution
1. Interference is the result of interaction of light coming from two different wavefronts originating from two coherent sources,whereas diffraction pattern is the result of interaction of light coming from different parts of the same wavefront.
2. In Interference, the fringes may or may not be of the same width; while in diffraction, the fringes are always of varying widths.
3. In Interference, the bright fringes are of the same intensity; while in diffraction, the bright fringes are of varying intensities.
RELATED QUESTIONS
A source emitting light of wavelengths 480 nm and 600 nm is used in a double-slit interference experiment. The separation between the slits is 0.25 mm and the interference is observed on a screen placed at 150 cm from the slits. Find the linear separation between the first maximum (next to the central maximum) corresponding to the two wavelengths.
In Young’s double-slit experiment, using monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by 5 x 10-2 m towards the slits, the change in the fringe width is 3 x 10-5 m. If the distance between the two slits is 10-3 m, calculate the wavelength of the light used.
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In Young's double slit experiment, the distance of the 4th bright fringe from the centre of the interference pattern is 1.5 mm. The distance between the slits and the screen is 1.5 m, and the wavelength of light used is 500 nm. Calculate the distance between the two slits.
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What is the interference pattern observed on the screen in Young's double-slit experiment?
