Question

A small aperture is illuminated with parallel beam of light having wavelength = 942 nm. If first minima is formed at an angular position of 1.5, then size of aperture is

Answer 1

theta = n × lambda / d (for dark)

where theta = angular position = 1.5

wavelength = lambda = 942 × 10^-9

n= 1 (first minima)

d = size of aperture.

now you can solve it by yourself...

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