E Nuclear and quantum physics

Practice questions on Nuclear and quantum physics

• Explain how the Franck–Hertz experiment provides evidence for the existence of discrete en… (4 marks, Explain)
• Explain how Heisenberg's uncertainty principle accounts for the fact that electrons cannot… (4 marks, Explain)
• Explain why the decay of a radioactive nucleus is described as a random and spontaneous pr… (4 marks, Explain)
• Explain why the half-life of a radioactive isotope is independent of the temperature of th… (4 marks, Explain)
• Explain why electrons emitted from a metal surface in the photoelectric effect have a rang… (4 marks, Explain)
• Explain why the existence of a threshold frequency in the photoelectric effect cannot be a… (4 marks, Explain)
• Explain why the existence of discrete atomic emission spectra provides evidence against th… (4 marks, Explain)
• Explain why the results of the Geiger–Marsden alpha-particle scattering experiment could n… (4 marks, Explain)
• Explain why electrons in an atom can only occupy discrete energy levels rather than a cont… (4 marks, Explain)
• Explain why the Bohr model of the hydrogen atom successfully predicts the wavelengths of s… (4 marks, Explain)
• Explain how the Davisson–Germer experiment provided evidence for the wave nature of electr… (4 marks, Explain)
• Explain how the de Broglie hypothesis accounts for the discrete energy levels observed in … (4 marks, Explain)
• Explain why the activity of a radioactive sample decreases over time, even though the deca… (4 marks, Explain)
• Explain why a graph of the number of undecayed nuclei N against time t for a radioactive s… (4 marks, Explain)
• Explain why two samples of the same radioactive isotope, one containing twice as many atom… (4 marks, Explain)