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1 | When two rocket ships A and B move toward each other at uniform speed, it is not possible for the astronauts on either ship to determine whether ship A is moving and ship B is at rest, ship B is moving and ship A is at rest, or both ships are moving. |
| A) | True |
| B) | False |
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2 | Einstein's second postulate tells us that the velocity of light is always constant. |
| A) | True |
| B) | False |
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3 | The kinetic energy of a particle traveling at relativistic speeds is equal to the difference between its total energy and its rest mass energy. |
| A) | True |
| B) | False |
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4 | In the photoelectric effect, a surface with a large work function is likely to produce photoelectrons with higher kinetic energy. |
| A) | True |
| B) | False |
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5 | de Broglie wavelengths can be calculated only for charged particles such as protons and electrons. |
| A) | True |
| B) | False |
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6 | The wavelengths from an emission spectrum of an element should not be expected to coincide with the wavelengths determined from an absorption spectrum of that element. |
| A) | True |
| B) | False |
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7 | The Balmer spectral series in an emission spectrum results from electrons in higher energy levels dropping to the ground state for the hydrogen atom. |
| A) | True |
| B) | False |
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8 | The stable electron orbits are those that contain an integral number of de Broglie wavelengths. |
| A) | True |
| B) | False |
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9 | The energy of an electron in the first excited states is 4 times its energy in the ground state. |
| A) | True |
| B) | False |
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10 | Rutherford's work with the scattering of alpha particles resulted in a nuclear theory of matter. |
| A) | True |
| B) | False |
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11 | According to the modern theory of relativity, newtonian mechanics is |
| A) | totally incorrect |
| B) | approximately correct for any velocity |
| C) | approximately correct for speeds much less than the speed of light |
| D) | correct for all velocities |
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12 | A clock of mass m and length L records a time interval Δt. If this clock moves with a velocity of 0.6c, which of the following statements is not true? |
| A) | The mass will be larger. |
| B) | The length will be shorter. |
| C) | The time interval will be longer. |
| D) | The time interval will be shorter. |
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13 | The rest mass of a proton is 1.673 x 10-27 kg. The relativistic mass of a proton when its velocity is 0.6c is approximately |
| A) | 1.3 x 10-27 kg |
| B) | 2.1 x 10-27 kg |
| C) | 2.6 x 10-27kg |
| D) | 8.4 x 10-27 kg |
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14 | What is the relativistic mass of an electron whose kinetic energy is 1.0 MeV? |
| A) | 35.6 x 10-31 kg |
| B) | 29.2 x 10-31 kg |
| C) | 26.9 x 10-31 kg |
| D) | 22.5 x 10-31 kg |
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15 | According to the Bohr theory of an atom, an electron may circle the nucleus indefinitely without radiating energy if |
| A) | the radius of its orbit is an integral multiple of the nuclear radius |
| B) | its orbital path is an integral number of de Broglie wavelengths |
| C) | its orbit is an integral multiple of its angular momentum |
| D) | the coulomb force is constant |
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16 | What is the de Broglie wavelength of an electron when it is accelerated through a potential difference of 200 V? |
| A) | 86.8 pm |
| B) | 62.2 pm |
| C) | 23.6 pm |
| D) | 6.92 pm |
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17 | For the hydrogen atom, which of the following energy-level transitions will result in the emission of a photon with the greatest frequency? |
| A) | From n = 2 to n = 1? |
| B) | From n = 1 to n = 4 |
| C) | From n = 4 to n = 2 |
| D) | From n = 3 to n = 1 |
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18 | The threshold frequency for a surface is known to be 5 x 1014 Hz. What is the wavelength of light required to eject a photoelectron having a kinetic energy of
5 eV? |
| A) | 120 nm |
| B) | 176 nm |
| C) | 211 nm |
| D) | 306 nm |
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19 | The energy of the photon emitted when an electron in the hydrogen atom drops from the n = 3 level to the n = 2 level is |
| A) | 10.2 eV |
| B) | 6.8 eV |
| C) | 1.89 eV |
| D) | 1.51 eV |
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20 | For objects traveling past an observer at relativistic speeds, the measurements of length are , the measurements of mass are , and the time intervals on the object are observed to be than when at rest. |
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21 | The is constant for all observers independent of their state of motion. |
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22 | The maximum kinetic energy of an ejected photoelectron is equal to the difference between the and . |
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23 | The lowest energy level in an atom is known as its state. |
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24 | Electron jumps from higher quantum levels back to the first or lowest quantum level produce the series for the hydrogen atom. Jumps back to the second level produce the series. |
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25 | If light from an incandescent platinum wire passes through sodium vapor before reaching the slit of a spectroscope, the resulting spectrum lacks the wavelength's characteristic of . Such a spectrum is known as a(n) spectrum. |
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26 | The is calculated by dividing Planck's constant by the product of the mass and velocity of a particle. |
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27 | The minimum energy required to eject a photoelectron from a surface is known as the . |