De Broglie’s Matter Waves
4.2 de Broglie’s Matter Waves
Learning Objectives
- Describe de Broglie’s hypothesis of matter waves
- Explain how the de Broglie’s hypothesis gives the rationale for the quantization of angular momentum in Bohr’s quantum theory of the hydrogen atom
- Describe the Davisson–Germer experiment
- Interpret de Broglie’s idea of matter waves and how they account for electron diffraction phenomena
Practice
| Practice 4.2.1 |
|---|
| The speed of proton A is larger than the speed of proton B. Which one has the longer wavelength? |
| A. proton A |
| B. proton B |
| C. both the same |
| D. neither has a wavelength |
| Practice 4.2.2 |
|---|
| An electron and a proton have the same speed. Which one has the longer wavelength? |
| A. electron |
| B. proton |
| C. both the same |
| D. neither has a wavelength |
| Practice 4.2.3 |
|---|
| An electron and a proton are accelerated through the same voltage. Which one has the longer wavelength? |
| A. electron |
| B. proton |
| C. both the same |
| D. neither has a wavelength |
Discuss!
For crystal diffraction experiments, wavelengths on the order of 0.20 nm are often appropriate. Find the energy (in eV) for a particle with this wavelength if the particle is
(a) a photon
(b) an electron
(c) an alpha particle
A neutron is shot straight up with an initial speed of 100 m/s. As it rises, does its de Broglie wavelength increase, decrease, or not change? Explain.
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