A small aperture is illuminated with a parallel beam of `lambda = 628 nm`. The emergent beam has an anglur divergence of `2^(@)`. The size of the aperture is

Options

A. 180 m
B. 18 `mu`m
C. 1.8 m
D. 0.18 m

Answer

B

Explanation

From diffraction at a single slit,
Size of aperture, `a=(lambda)/(sin theta)`
`or a=(3141.59xx10^(-10))/(sin1^(@))=18xx10^(-6)m=18mu m`