Question

In young's double slit experiment, light of wavelength 6000 angstrom is used to get an interference pattern on a screen. The fringe width changes by 1.5 mm when the screen is brought towards the double slit by 50 cm. find the distance between the two slits.

Answer 1

Dear Student ,
Here the given data is :
$$\begin{gathered} fringewidth,\beta =1·5mm \\ D=50cm \\ d=? \\ \lambda =6000\stackrel{0}{A} \\ Therefore,distancebetweentwoslitsis, \\ d=\frac{\lambda D}{\beta }=\frac{6000\times {10}^{-8}\times 50}{0·15}=0·02cm \end{gathered}$$
Regards