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Grade 8General Physics

In a double-slit experiment the angular width of a fringe is found to be 0.2° on a screen placed 1 m away. The wavelength of light used is 600 nm. What will be the angular width of the fringe if the entire experimental apparatus is immersed in water? Take refractive index of water to be 4/3.

Profile image of prasanjeet kumar
12 Years agoGrade 8
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1 Answer

Profile image of Bhum oli
9 Years ago
  • \thetaw = \thetaa  × \muw
  • \thetaw = 0.2’ ×  4/3 = 0.267’
\thetaa = \betaa /d 
but  \betaw =\betaa/\muw
we know that angular width is  the ratio of fring width and slit width
but if  slit is immersed in water from air then frings width in water is ratio of fing width in air and refractive index of water