Lawrence Bragg begins by outlining the two contesting theories of light held in the eighteenth century: the particles theory and the wave theory. This he follows with a description and demonstration of Thomas Young’s famous pinhole experiment; an experiment that validated the wave theory. Bragg then turns to diffraction, showing its effects with the use of Young’s original wave trough of 1800 and explaining interference fringes through a series of fascinating demonstrations.
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Full list of Properties of Matter films
Young and the wave theory of light
Reflection, refraction and polarization of light