Question

In Young's double-slit experiment, the angular width of a fringe formed on a distant screen is $1^o$. The wavelength of light used is $6000\mathring{A}$. What is the spacing between the slits?

• A. $344mm$
• B. $0.1344mm$
• C. $0.0344mm$
• D. $0.034mm$

Answer 1

Answer: (C)

$0.0344mm$

Angular fringe width: ${\beta }_{\theta }=\frac{\lambda }{d}=\frac{6000\times {10}^{-10}}{d}$
$\therefore d=\frac{6\times {10}^{-7}}{\frac{1\times \pi }{180}}=0.344\times {10}^{-4}m=0.0344m$