Past exam of the physics A course of the University of Cambridge / 2011 / Paper 1 / Section B / B8 / b (slit width) / Solution

With $w=1.5\mu \mathrm{m}$ the same principal maxima sit inside a narrower envelope, whose first zeros are at $s=\pm 10/3$. The third order is now close to a zero and is strongly suppressed, whereas the central peak is taller. The first exact missing nonzero integer orders are $m=\pm 10$; $m=3$ is suppressed rather than identically missing.