PSI AP Physics 2 Name 1. The Cathode Ray Tube experiment is associated with: (A) J. J. Thomson (B) J. S. Townsend (C) M. Plank (D) A. H. Compton 2. The electron charge was measured the first time in: (A) Cathode ray experiment (B) Photoelectric effect experiment (C) Oil drop experiment (D) Compton effect experiment 3. What is the difference between cathode rays and X-rays? (A) Both rays are made up of particles. (B) Both rays are different types of electromagnetic radiation. (C) Cathode rays are particles and X-rays are electromagnetic radiation. (D) Cathode rays are electromagnetic radiation and X-rays are particles. 4. What distinctive phenomena are illustrated in X-ray spectra? (Select 2 answers) (A) Bremsstrahlung - deceleration of the electrons striking the anode. (B) Acceleration of the electrons after they strike the anode. (C) Internal atomic structure of the anode. (D) Cathode ray penetration power. 5. Which of the following colors indicates an object of the lowest temperature? (A) Violet (B) Blue (C) Yellow (D) Red 6. Which is a property of a black body radiator? (A) It absorbs all incident radiation, then re-emits it at a frequencies determined by its temperature. (B) It is always black, even when heated to high temperatures. (C) It absorbs all incident radiation and does not re-emit any radiation. (D) As it is heated, it changes color from black to blue to red.
7. Which of the following photons has the greatest energy? (A) Infrared (B) Blue (C) γ- photon (D) ultraviolet photon 8. What discrepancy between experiment and theory helped lead Max Planck to his quantum theory? (A) The discovery of Cathode Rays. (B) The discovery of X-Rays. (C) The Ultraviolet Catastrophe. (D) The discovery of electrons. 9. The energy of a photon depends on: (A) Amplitude (B) Speed (C) Temperature (D) Frequency 10. How does the energy of a photon change if the wavelength is doubled? (A) Energy doubles (B) Energy quadruples (C) Energy stays the same (D) Energy is halved 11. How does the momentum of a photon change if the wavelength is halved? (A) Doubles (B) Quadruples (C) Stays the same (D) Is cut to one-half 12. The photoelectric effect explains: (A) The wave nature of light (B) The particle nature of light (C) The wave properties of an electron (D) The atomic structure
13. The kinetic energy of photo-electrons depends on (Select 2 answers): (A) Angle of illumination (B) Intensity of light (C) Work function (D) Wavelength of light 14. Which of the following is the formula of the photon momentum? (A) p = hf/c (B) p = cλ/h (C) p = hc/f (D) p = E/mc 15. The stopping potential of photo-electrons depends on which of the following (Select 2 answers) (A) The light intensity (B) The frequency of the photons (C) The composition of the metal surface (D) The speed of the incoming photons 16. Which of the following formulas expresses the photoelectric effect? (A) hλ = W 0 + KE (B) hf = W 0 - KE (C) hf = W 0 + KE (D) hλ = -W 0 + KE 17. Which of the following graphs correctly relates the maximum kinetic energy of photo-electrons and the frequency of the incident light? (A) (B) (C) (D) 18. Which of the following graphs correctly relates the maximum kinetic energy of photo-electrons and the intensity of the incident light? intensity intensity intensity intensity (A) (B) (C) (D)
19. Which of the following graphs correctly relates the de Broglie wavelength and the linear momentum of a particle? (A) (B) (C) (D) 20. All of the following are properties of γ-rays EXCEPT: (A) They discharge electrified objects (B) They ionize gases (C) They are deflected by magnetic fields (D) They penetrate objects 21. Which of the following phenomena provides the best evidence that light can have particle properties? (A) Diffraction of light (B) Compton scattering (C) Electron diffraction (D) γ-ray diffraction 22. Which of the following phenomena provides the best evidence that particles can have wave properties? (A) The absorption of photons by electrons in an atom (B) The interference pattern produced by neutrons incident on a crystal (C) The production of x-rays by electrons striking a metal target (D) Compton scattering 23. Which of the following formulas can be used to determine the de Broglie wavelength? (A) λ = hmv (B) λ = h/mv (C) λ = mv/h (D) λ = mc/h 24. A photon can disappear producing an electron and positron. What is this phenomenon called? (A) X-Rays diffraction (B) Electron scattering (C) Annihilation (D) Pair production
25. When a proton collides with an antiproton they disappear producing photons. This phenomenon is called (A) X-Rays diffraction (B) Electron scattering (C) Annihilation (D) Pair production 26. The following statement: In order to understand a given experiment, we must use either the wave or particle theory, but not both is called? (A) Wave theory of light (B) Particle theory of light (C) Principle of complementarity (D) Wave theory of matter 27. Electrons are accelerated to a maximum speed of v in an X-Ray tube by an applied voltage V 0. What is the maximum speed of the electrons if the voltage is quadrupled? (A) 4v (B) 2v (C) 2 v (D) v/4 28. In a Compton Effect experiment a photon scattered from an electron at rest increases its wavelength. Which of the following deflection angles θ provides the greatest increase in the wavelength of the scattered photon? (A) 0 (B) 60 (C) 90 (D) 180 29. If all of the following objects move at the same speed, which one will have the greatest debroglie wavelength? (A) Neutron (B) Electron (C) Bowling ball (D) α- Particle 30. Rutherford s Scattering α particles by a gold foil experiment disproved which of the following: (A) Plum-pudding model of the atom (B) Planetary model of the atom (C) De Broglie hypothesis (D) Wave nature of light
31. In Rutherford s experiment, most of α particles pass through the foil without deflection. Which of the following properties of the atom can be explained by this observation? (Select 2 answers) (A) An atom s positive charge is concentrated in the nucleus (B) The nucleus is made up neutrons and protons (C) Electrons move around the nucleus in orbits of quantized energy and angular momentum (D) An atom is mostly empty space 32. Which of the following statement(s) can be associated with Bohr s theory of the atom? (Select 2 answers) (A) An electron orbiting the nucleus can change its energy continuously (B) An electron orbiting the nucleus emits energy and falls on the nucleus (C) An electron can change its energy only by a certain portion when it jumps between the orbits (D) The angular momentum of an electron around the nucleus is equal an integer times h/2π 33. When an electron falls from an orbit the first excited state (n=2) to the ground state (n=1): (A) A photon is emitted (B) A photon is absorbed (C) No photons are involved (D) An electron is emitted 34. In the Bohr model, when an electron jumps from the n = 1 orbit (of radius r 1) to the n = 3 orbit, what is its new orbital radius as a proportion of r 1? (A) r 1/9 (B) r 1/3 (C) 3 r 1 (D) 9 r 1 35. In the Bohr model, when an electron jumps from the n = 1 orbit (of energy E 1) to the n = 4 orbit, what is its new energy as a proportion of E 1? (A) E 1/9 (B) E 1/16 (C) 4 E 1 (D) 16 E 1 36. In the Bohr model, when an electron orbits a single proton in the n = 5 state, how many debroglie wavelengths fit onto the circumference of this orbit? (A) 3 (B) 4 (C) 5 (D) 6
37. An electron accelerated from rest by a 600V potential difference has a De Broglie wavelength of λ. What would the electron s De Broglie wavelength be if the potential difference had been 150 V? (A) 2 λ (B) λ /2 (C) λ /4 (D) 4 λ 38. According to Maxwell s theory of electromagnetism, an electron orbiting a nucleus must: (A) Change its energy in quantized amounts (B) Conserve its angular momentum (C) Conserve its energy (D) Radiate its energy 39. A hypothetical atom has energy levels as shown by the graph (right). An electron is excited from the ground state to the -1 ev energy level. Which of the following are the energies of the emitted photons? (Select 2 answers) (A) 2 ev (B) 4 ev (C) 10 ev (D) 11 ev 40. A container is filled with a gas consisting of atoms in the ground state. The energy energy level diagram for the atoms is shown on the right. The gas is irradiated with electromagnetic radiation with the energy range from 4 ev to 9 ev. Which set of photon energies might be found in the emission spectrum. (A) 1 ev, 2 ev, and 6 ev (B) 2 ev, 3 ev, and 4 ev (C) 1 ev, 3 ev, and 5 ev (D) 7 ev, 8 ev, and 9 ev 41. A container is filled with a gas consisting of atoms in the ground state. The energy energy level diagram for the atoms is shown on the right. The gas is irradiated with electro-magnetic radiation with the energy range from 4 ev to 9 ev. Which of the following transitions will produce a photon with the longest wavelength? (A) From n = 4 to n = 1 (B) From n = 2 to n = 1 (C) From n = 3 to n = 1 (D) From n = 4 to n = 3
42. According to the Bohr s theory of the hydrogen atom, electrons starting in the 4 th energy level and eventually ending in the ground state could produce a total of how many different spectral lines? (A) 3 (B) 4 (C) 6 (D) 9
Multiple Choice Answers 1. A 2. C 3. C 4. A,C 5. D 6. A 7. C 8. C 9. D 10. D 11. A 12. B 13. C,D 14. A 15. B,C 16. C 17. C 18. A 19. D 20. B 21. B 22. B 23. B 24. D 25. C 26. C 27. B 28. D 29. B 30. A 31. A,D 32. C,D 33. A 34. D 35. B 36. C 37. D 38. D 39. B,C 40. C 41. D 42. C