Question

A Young’s double slit experiment is conducted with slit separation 10mm, where the screen is 2m away from the slits. If wavelength of light used is 6000Å , then fringe width in 'mm' is

• A. $0.12$
• B. $0.24$
• C. $0.36$
• D. $0.48$

Answer 1

Answer: (A)

$0.12$

fringe width $\left(\beta \right)=\frac{D\lambda }{d}$
$=\frac{2\times 6000\times {10}^{-10}}{10\times {10}^{-3}}$
$=12\times {10}^{-5}$
$=0.12\times {10}^{-3}m$
$=0.12mm.$