Question

The diffraction produced by a barrier is similar to that of a single slit of the same size. What is the distance observed between two diffraction minima of order m = ±9 (one on each side of the central maximum) caused by a wire of diameter 1.23 mm? The wire is illuminated by a laser with wavelength 574 nm and the viewing screen is at a distance of 2.2 m from the wire. Give your answer in cm, but enter only the numerical part in the box.

Answer 1

Solution:

Location of mth minima from the central maxima is given by

(1)

Given that:

Putting these values in equation (1), we find

(2)

Similarly,

(3)

So, the distance between two central minima of order is given by

(4)

putting the values from equations (2) and (3) in (4), we find