The first 25 years of the twentieth century were momentous for the rapid pace of change in scientists' understanding of the nature of matter.
(a) How did Rutherford's experiments on the scattering of α particle by a gold foil set the stage for Bohr's theory of the hydrogen atom?
(b) In what ways is de Broglie's hypothesis, as it applies to electrons, consistent with J. J. Thomson's conclusion that the electron has mass? In what sense is it consistent with proposals preceding Thomson's work that the cathode rays are a wave phenomenon?