Question

Physics - Single Slit Differaction

Light from a distant point source is incident on a narrow slit. Each of the graphs below shows the intensity on a distant screen as a function of theta. The only difference among the six physical situations is the width of the slit. The horizontal scale is the same for all graphs. The vertical scale has been normalized so that the maximum intensity is the same for all cases. Rank the cases according to the width of the slit, from largest to smallest. Explain. In sections 1 and 2 of the tutorial A model for single-slit diffraction, you developed a method for determining the angle to the first minimum in a single-slit diffraction pattern. In this homework, the method will be extended and applied to determine the locations of the higher-order minima. Monochromatic light from a distant point source passes through a mask that contains four identical very narrow evenly-spaced slits.

Answer 1

Here maximum intensity is same for all. Curve produced by largest slit is DT And smallest one is AT So, The slit goes smaller as the angle become larger or vice versaT caseD > caseB caseF> caseC caseE > caseA

Answer 2

We need to rank accoding to the width of the slits, we know that the width of the slits goes smaller as the angle become larger or vice versa.

From the above figure,
$\theta$ is larger for case A>case E>case C>case F>case B>case D,

Since $\theta$ is inversally propotional to width we can arrange the largest to smallest width as
caseD>case B>case F>case C> caseE>case A.