Using Young's double slit experiment, a monochromatic light of wavelength 5000 $\mathop A\limits^o$ produces fringes of fringe width 0.5 mm. If another monochromatic light of wavelength 6000 $\mathop A\limits^o$ is used and the separation between the slits is doubled, then the new fringe width will be :
Solution
<p>Fringe width = ${{\lambda D} \over d}$</p>
<p>$\Rightarrow$ Fringe width $\propto$ ${\lambda \over d}$</p>
<p>$\Rightarrow$ New fringe width = 0.5 mm $\times {{1.2} \over 2} = 0.3$ mm</p>
About this question
Subject: Physics · Chapter: Optics · Topic: Reflection and Mirrors
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