Chapter 19.2, Problem 26SSC

To determine

To sketch:The pattern that would be seen on the screen for the given illumination.

Explanation of Solution

Introduction:

Diffraction of light waves is the bending of light waves around the edges of an obstacle. This illuminates the region where the geometrical shadow of the obstacle is expected. As the light wave encounters the slits there will be a diffraction of light waves from the slits. Also, the interference takes place between the light waves that are diffracted from the slits. The interference may be constructive or destructive. For constructive interference, the band produced in the pattern is bright and for the destructive interference, the region is dark in the pattern. The diffraction pattern can be seen on a screen placed far from the slits.

The bands in the diffraction pattern produced in this situation are equidistant and parallel to each other. But the bright bands are considerably thinner and are separated by broader dark bands as shown in the figure 1.

  

Figure 1