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Question
Explain De Broglie’s Hypothesis.
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Solution
- De Broglie proposed that a moving material particle of total energy E and momentum p has a wave associated with it (analogous to a photon).
- He suggested a relation between properties of the wave, like frequency and wavelength, with that of a particle, like energy and momentum.
p = `"E"/"c" = "hv"/"c" = "h"/lambda` - Thus, the frequency and wavelength of a wave associated with a material particle, of mass m moving with a velocity v, are given as
`"v" = "E"/"h"` and `lambda = "h"/"p" = "h"/"mv"` ….(1) - De Broglie referred to these waves associated with material particles as matter waves. The wavelength of the matter waves, given by equation (1), is now known as de Broglie wavelength and the equation is known as de Broglie relation.
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