In a single-slit diffraction experiment, a beam of monochromatic light passes through a slit of width 11.0 μm. If the first order dark fringe of the resulting diffraction pattern is at an angle of 4.31°, what is the wavelength of light?
A) 827 nm
B) 301 nm
C) 602 nm
D) 402 nm
E) 201 nm

Question

Quizplus · Accepted Answer

The position of the first order dark fringe in a single-slit diffraction pattern is given by the equation $ a \sin \theta = m \lambda $, where $ a $ is the slit width, $ \theta $ is the angle, $ m $ is the order number (1 for first order), and $ \lambda $ is the wavelength. Solving for $ \lambda $ with $ a = 11.0 \, \mu m $, $ \theta = 4.31^\circ $, and $ m = 1 $, we find $ \lambda \approx 827 \, nm $.

In a Single-Slit Diffraction Experiment, a Beam of Monochromatic Light