Physics HW Chapters 383940 (Due May 23, Test May 28)

Physics HW Chapters 383940 (Due May 23, Test May 28)

Multiple Choice

Identify the choice that best completes the statement or answers the question.

____ 1. Light behaves as a

a. / wave.
b. / particle.
c. / both A and B
d. / none of the above

____ 2. The energy of a photon is directly proportional to its

a. / speed.
b. / amplitude.
c. / period.
d. / frequency.
e. / wavelength.

____ 3. The photoelectric effect occurs when

a. / light is reflected from a metal surface.
b. / high-frequency light shines on certain metal surfaces.
c. / low-frequency light shines on certain metal surfaces.
d. / all of the above

____ 4. The photoelectric effect best demonstrates the

a. / particle nature of light.
b. / wave nature of light.
c. / both A and B
d. / none of the above

____ 5. In the photoelectric effect, the brighter the illuminating light on a photosensitive surface, the greater the

a. / velocity of ejected electrons.
b. / number of ejected electrons.
c. / both A and B
d. / none of the above

____ 6. A photocell can be activated with blue light but not with red light. This is because blue light has

a. / a longer wavelength than red light.
b. / a higher speed than red light.
c. / a higher frequency than red light.
d. / a stronger electric field than red light.
e. / none of the above.

____ 7. The photoelectric effect occurs when the incident light beam is

a. / either dim or bright.
b. / bright.
c. / dim.

____ 8. Which of the following photons have the greatest energy?

a. / blue light
b. / yellow light
c. / green light
d. / red light
e. / ultraviolet

____ 9. When light shines on a photosensitive material

a. / electrons are always ejected.
b. / electrons may be ejected.
c. / protons are always ejected.
d. / protons may be ejected.
e. / none of the above

____ 10. The number of electrons ejected in the photoelectric effect depends on the light beam's

a. / amplitude.
b. / speed.
c. / frequency.
d. / intensity.
e. / wavelength.

____ 11. A photosensitive surface is illuminated with both blue and violet light. The light that will cause more electrons to be ejected is the

a. / blue light.
b. / violet light.
c. / Both eject the same number.
d. / Not enough information is given.

____ 12. The wavelength of a particle is related to the particle's

a. / potential energy.
b. / size.
c. / name.
d. / momentum.
e. / all of the above

____ 13. Diffraction effects cannot be measured for

a. / water waves.
b. / baseballs.
c. / electrons.
d. / low-frequency light.
e. / high-frequency light.

____ 14. Electron wavelengths, in general, are

a. / the same as light wavelengths.
b. / shorter than light wavelengths.
c. / longer than light wavelengths.

____ 15. When an atomic electron goes from a high-energy state to a low-energy state, it

a. / emits a photon.
b. / absorbs a photon.
c. / neither absorbs nor emits a photon.

____ 16. The discrete orbits of electrons are best understood by considering the electron's

a. / charge.
b. / particle properties.
c. / quantum properties.
d. / wave properties.

____ 17. When an electron in an atom emits a photon, the

a. / atom gains energy exactly equal to the energy of the photon.
b. / electron spirals closer to the nucleus.
c. / electron's energy decreases by exactly the energy of the photon.
d. / charge on the atom decreases by one.
e. / electron spirals farther from the nucleus.

____ 18. Compared to the innermost electrons of a uranium atom, the innermost electron of a hydrogen atom is

a. / closer to the nucleus.
b. / the same distance from the nucleus.
c. / farther from the nucleus.

____ 19. The ratio of a photon's energy to its frequency is

a. / its wavelength.
b. / its speed.
c. / Planck's constant.
d. / its amplitude.
e. / none of the above

____ 20. In the Bohr model of hydrogen, discrete radii and energy states result when an electron circles the atom in an integral number of

a. / wave frequencies.
b. / de Broglie wavelengths.
c. / quantum numbers.
d. / diffraction patterns.
e. / none of the above

____ 21. Compared to the diameter of a zirconium atom (40 protons), the diameter of a mercury atom (80 protons) is approximately

a. / one quarter as large.
b. / one half as large.
c. / the same size.
d. / twice as large.
e. / four times as large.

____ 22. The Bohr model of the atom accounts for

a. / the mystery of atomic spectra.
b. / predicted properties of hydrogen.
c. / X-rays emitted in electron transitions.
d. / general chemical properties of the elements.
e. / all of the above

____ 23. In quantum mechanics, one normally studies

a. / what happens when light shines on a metallic surface.
b. / the structure of light quanta.
c. / the structure of atoms by treating light and particles as waves.
d. / the mechanics of fast-moving objects such as cosmic rays.

____ 24. Planck's constant is a basic constant of nature that

a. / formulates the relationship between mass and energy.
b. / relates the energy of a photon to its momentum.
c. / is the foundation of the correspondence principle.
d. / sets an upper limit on the size of things.
e. / sets a lower limit on the size of things.

____ 25. Orbital electrons do not spiral into the nucleus. This is because of

a. / the large nuclear size compared to the electron's size.
b. / the wave nature of the electron.
c. / angular momentum conservation.
d. / electromagnetic forces.
e. / none of the above

____ 26. The electrical force between an inner electron and the nucleus of an atom is

a. / larger for atoms of low atomic number.
b. / larger for atoms of high atomic number.
c. / the same for all atoms.

____ 27. An excited atom decays to its ground state and emits a photon of green light. If, instead, the atom decayed to an intermediate state, then the light emitted could be

a. / blue.
b. / red.
c. / violet.
d. / any of the above.
e. / none of the above.

____ 28. An electron and a baseball move at the same speed. Which has the longer wavelength?

a. / the baseball
b. / the electron
c. / Both have the same wavelength.

____ 29. A hypothetical atom has four distinct energy states. Assuming all transitions are possible, how many spectral lines can this atom produce?

a. / 3
b. / 4
c. / 5
d. / 6
e. / more than 6

____ 30. An electron and a proton are traveling at the same speed. Which has a longer wavelength?

a. / Both have the same wavelength.
b. / the proton
c. / the electron

____ 31. Which of the following has the longer wavelength?

a. / A low-energy electron
b. / A high-energy electron
c. / Both have the same wavelength.

____ 32. The photoelectric effect is more effective with violet light than with red light because the photons of violet light

a. / resonate with the atoms in the material.
b. / deliver more energy to the material.
c. / are more numerous.
d. / none of the above.

____ 33. The degree to which a system is predictable depends on knowledge of

a. / whether or not the system is Newtonian or quantum.
b. / initial conditions.
c. / both A and B

____ 34. Which of the following is more chaotic?

a. / weather
b. / heat transfer between thermal conductors
c. / electric current in an AC circuit
d. / collision between two pool balls

____ 35. The nucleus of an atom consists of

a. / protons, neutrons, and electrons.
b. / protons.
c. / protons and electrons.
d. / neutrons and electrons.
e. / protons and neutrons.

____ 36. X-rays are similar to

a. / alpha rays.
b. / beta rays.
c. / gamma rays.
d. / all of the above
e. / none of the above

____ 37. Electrical forces within an atomic nucleus tend to

a. / push it apart.
b. / hold it together.
c. / none of the above

____ 38. Generally speaking, the heavier a nucleus is, the more it is

a. / unstable.
b. / stable.
c. / neither stable nor unstable.

____ 39. Which of the following is NOT emitted in radioactive decay?

a. / electrons
b. / high-energy electromagnetic radiation
c. / beta rays
d. / alpha particles
e. / all of the above

____ 40. When alpha and beta rays pass through a magnetic field, their paths change

a. / not at all.
b. / in opposite directions.
c. / in the same direction.

____ 41. Which radiation has no electric charge associated with it?

a. / gamma rays
b. / alpha rays
c. / beta rays
d. / all of the above
e. / none of the above

____ 42. Which experiences the least electrical force in an electric field?

a. / a beta particle
b. / a proton
c. / an alpha particle
d. / a gamma ray
e. / same force for all of the above

____ 43. Which experiences the greatest electrical force in an electric field?

a. / an alpha particle
b. / a gamma ray
c. / a beta particle
d. / a proton
e. / same force for all of the above

____ 44. An atom is called an ion if there

a. / is an uneven number of protons and electrons.
b. / are more neutrons than protons.
c. / is an uneven number of neutrons and electrons.
d. / is an uneven number of neutrons and protons.
e. / none of the above

____ 45. The atomic number of an atom or ion refers to the number of

a. / nucleons.
b. / electrons.
c. / neutrons.
d. / protons.
e. / neutrons, protons, and electrons.

____ 46. The atomic mass number of an atom refers to the number of

a. / neutrons.
b. / nucleons.
c. / protons.
d. / electrons.
e. / neutrons, protons, and electrons.

____ 47. Deuterium

a. / can become part of a molecule called heavy water.
b. / is an isotope of hydrogen.
c. / consists of one proton and one neutron.
d. / is stable.
e. / all of the above

____ 48. Large nuclei like uranium are radioactive because

a. / they have too much mass.
b. / they are too large for the strong force to counteract electrostatic repulsion.
c. / there are too many protons.
d. / they can hold extra particles, such as beta rays.
e. / none of the above

____ 49. The time needed for half of a radioactive sample to decay is called its

a. / transmutation time.
b. / period.
c. / decay period.
d. / half-life.

____ 50. The half-life of a certain isotope is 1 day. At the end of 4 days, how much of the isotope remains?

a. /
b. /
c. / none of it
d. /
e. / none of the above

____ 51. The half-life of most radioactive isotopes is about

a. / 4.5 billion years.
b. / 5700 years.
c. / a few seconds.
d. / a few years.
e. / too variable for any generalization.

____ 52. Artificially induced radioactive elements generally have relatively

a. / medium-length half lives.
b. / long half lives.
c. / short half lives.

____ 53. Carbon-14 is radioactive and decays into

a. / carbon-12.
b. / oxygen-14.
c. / carbon-13.
d. / nitrogen-14.
e. / none of the above

____ 54. The reason carbon dating works is that

a. / there is so much non-radioactive carbon dioxide in the air.
b. / when a plant or animal dies, it stops producing oxygen.
c. / plants and animals are such strong emitters of carbon-14.
d. / after a plant or animal dies, it stops taking in fresh carbon-14.
e. / none of the above

____ 55. Radioactive tracers can be used to help

a. / engineers study how parts of a car withstand wear.
b. / farmers use the proper amount of fertilizer.
c. / public utility workers trace leaks in buried pipes.
d. / doctors trace food as it moves through the body.
e. / all of the above

____ 56. Carbon-14 is produced in the atmosphere primarily by

a. / photosynthesis.
b. / cosmic ray bombardment.
c. / nitrogen bombardment.
d. / plants and animals.
e. / none of the above

____ 57. Carbon dating requires that the object being tested contain

a. / sugar molecules.
b. / inorganic material.
c. / charcoal.
d. / organic material.
e. / none of the above

____ 58. Most radiation we are exposed to comes from

a. / nuclear power plants.
b. / weapons-testing fallout.
c. / cosmic rays and earth minerals.
d. / medical X-rays.
e. / none of the above

____ 59. Which type of radioactive decay occurs when the atomic number increases by one?

a. / beta decay
b. / alpha decay
c. / positron decay
d. / gamma decay

____ 60. When a nucleus emits a beta particle, its atomic number

a. / changes, and so does its mass number.
b. / changes, but its mass number remains constant.
c. / remains constant, and so does its mass number.
d. / remains constant, but its mass number changes.
e. / none of the above.

____ 61. When uranium (92 protons) ejects an alpha particle, the nucleus left behind has

a. / 92 protons.
b. / 91 protons.
c. / 90 protons.
d. / 89 protons.
e. / 88 protons.

____ 62. When thorium (90 protons) ejects a beta particle, the resulting nucleus has

a. / 87 protons.
b. / 88 protons.
c. / 89 protons.
d. / 90 protons.
e. / none of the above

____ 63. When a nucleus emits a positron, its atomic number

a. / doesn't change.
b. / increases by 1.
c. / decreases by 1.

____ 64. An element will decay to another element with higher atomic number in the periodic table if it emits

a. / a proton.
b. / an alpha particle.
c. / a beta particle.
d. / a gamma ray.
e. / none of the above

____ 65. In order for an atom to decay to an element that is one greater in atomic number, it can emit