RAD 121 EXAM #1 QUESTIONS WITH VERIFIED
ANSWERS
b. November 8, 1895 - Answers - 1. When were x-rays discovered?
a. October 8, 1985 b. November 8, 1895
c. January 23, 1896 d. August 15, 1902
c. 15 min. - Answers - 5. The first radiograph produced by Roentgen, of his wife's hand,
required an exposure time of:
a. 15 s.
b. 150 s.
c. 15 min.
d. 150 min.
a. reddening of the skin. - Answers - 9. Erythema, an early sign of biologic damage due
to x-ray exposure, is:
a. reddening of the skin.
b. a malignant tumor.
c. a chromosomal change.
d. one of the most serious effects of x-ray exposure.
a. angstroms. - Answers - 12. X-rays used in radiography have wavelengths that are
measured in:
a. angstroms.
b. millimeters.
c. centimeters.
d. hertz
c. roentgenology. - Answers - 17. When first developed, the branch of medicine using x-
rays was called:
a. radiology.
b. radiography.
c. roentgenology. d. imaging sciences.
b. 10−10 meter - Answers - 20. An angstrom (Å) is equal to:
a. 10−1 meter
b. 10−10 meter
c. 10−1 foot
d. 10−10 foot
d. 3 × 1018 Hz - Answers - 22. X-rays used in radiography have wavelengths ranging
from 3 × 1019 to:
a. 3 × 108 Hz.
, b. 3 × 10−10 Hz.
c. 3 × 1010 Hz.
d. 3 × 1018 Hz
d. electron volts (eV). - Answers - 25. The energy of an individual x-ray photon is
measured in:
a. frequency.
b. wavelength.
c. kilovolts peak (kVp).
d. electron volts (eV).
c. heterogeneous. - Answers - An x-ray beam that has photons with many different
energies is:
a. homogenous.
b. monoenergetic. c. heterogeneous. d. never found.
d. All options are correct. - Answers - 27. X-rays can:
a. penetrate the human body and be absorbed in the human body
b. penetrate the human body and change direction in the human body
c. be absorbed in the human body and change direction in the human body
d. All options are correct.
c. dose equivalent - Answers - 28. Which of the following units is used to measure
occupational radiation exposure?
a. exposure
b. radioactivity
c. dose equivalent d. effective dose
d. effective dose - Answers - 29. What radiation unit is defined as an expression of the
relative risk to humans of exposure to ionizing radiation? a. exposure
b. radioactivity
c. dose equivalent d. effective dose
False: X-rays are electrically neutral - Answers - TRUE/FALSE: 2. X-rays carry a
negative charge that causes ionization.
a. cathode - Answers - 1. The _____ is the portion of the x-ray tube that contains the
filament.
a. cathode
b. anode
c. rotor
d. rotating disk
a. tungsten. - Answers - 2. The cathode filament is made of: a. tungsten.
b. rhenium.
c. molybdenum.
ANSWERS
b. November 8, 1895 - Answers - 1. When were x-rays discovered?
a. October 8, 1985 b. November 8, 1895
c. January 23, 1896 d. August 15, 1902
c. 15 min. - Answers - 5. The first radiograph produced by Roentgen, of his wife's hand,
required an exposure time of:
a. 15 s.
b. 150 s.
c. 15 min.
d. 150 min.
a. reddening of the skin. - Answers - 9. Erythema, an early sign of biologic damage due
to x-ray exposure, is:
a. reddening of the skin.
b. a malignant tumor.
c. a chromosomal change.
d. one of the most serious effects of x-ray exposure.
a. angstroms. - Answers - 12. X-rays used in radiography have wavelengths that are
measured in:
a. angstroms.
b. millimeters.
c. centimeters.
d. hertz
c. roentgenology. - Answers - 17. When first developed, the branch of medicine using x-
rays was called:
a. radiology.
b. radiography.
c. roentgenology. d. imaging sciences.
b. 10−10 meter - Answers - 20. An angstrom (Å) is equal to:
a. 10−1 meter
b. 10−10 meter
c. 10−1 foot
d. 10−10 foot
d. 3 × 1018 Hz - Answers - 22. X-rays used in radiography have wavelengths ranging
from 3 × 1019 to:
a. 3 × 108 Hz.
, b. 3 × 10−10 Hz.
c. 3 × 1010 Hz.
d. 3 × 1018 Hz
d. electron volts (eV). - Answers - 25. The energy of an individual x-ray photon is
measured in:
a. frequency.
b. wavelength.
c. kilovolts peak (kVp).
d. electron volts (eV).
c. heterogeneous. - Answers - An x-ray beam that has photons with many different
energies is:
a. homogenous.
b. monoenergetic. c. heterogeneous. d. never found.
d. All options are correct. - Answers - 27. X-rays can:
a. penetrate the human body and be absorbed in the human body
b. penetrate the human body and change direction in the human body
c. be absorbed in the human body and change direction in the human body
d. All options are correct.
c. dose equivalent - Answers - 28. Which of the following units is used to measure
occupational radiation exposure?
a. exposure
b. radioactivity
c. dose equivalent d. effective dose
d. effective dose - Answers - 29. What radiation unit is defined as an expression of the
relative risk to humans of exposure to ionizing radiation? a. exposure
b. radioactivity
c. dose equivalent d. effective dose
False: X-rays are electrically neutral - Answers - TRUE/FALSE: 2. X-rays carry a
negative charge that causes ionization.
a. cathode - Answers - 1. The _____ is the portion of the x-ray tube that contains the
filament.
a. cathode
b. anode
c. rotor
d. rotating disk
a. tungsten. - Answers - 2. The cathode filament is made of: a. tungsten.
b. rhenium.
c. molybdenum.
