Question

In the diffraction pattern due to a single slit linear width of the central max will be twice that of slit width $(d)$. The distance between the slit and the screen is

• A. $\frac{\lambda^2}{d} $
• B. $\frac{d^2}{\lambda} $
• C. $\frac{2\lambda^2}{d} $
• D. $\frac{2d^2}{\lambda} $

Answer 1

Answer: (B)

Width of central maxima due to single slit diffraction is given by,
$\beta = \frac{2 \lambda D}{d} $
Here, $\beta = 2 d$
So, $2 d = \frac{ 2 \lambda D}{d} $ or $D = \frac{d^2}{\lambda}$