Test Bank For Dental Radiography Principles and Techniques
6th Edition, Joen Iannucci, Laura Howerton Complete Guide
Chapter 02: Radiation Physics
Iannucci: Dental Radiography, 6th Edition
MULTIPLE CHOICE
1. The fundamental unit of matter is the
a. proton.
b. neutron.
c. electron.
d. atom.
ANS: D
A proton is a subatomic particle; the fundamental unit of matter is the atom. A neutron is
a subatomic particle; the fundamental unit of matter is the atom. An electron is a
subatomic particle; the fundamental unit of matter is the atom. The fundamental unit of
matter is the atom.
DIF: Recall REF: Page 8 OBJ: 1
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
2. The nucleus of an atom contains
a. protons.
b. neutrons.
c. protons and neutrons.
d. electrons.
ANS: C
The nucleus of an atom contains neutrons as well as protons. The nucleus of an atom
contains protons as well as neutrons. The nucleus of an atom contains protons and
neutrons. The nucleus of an atom does not contain electrons; it contains protons and
neutrons.
DIF: Recall REF: Page 8 OBJ: 2
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
3. Which subatomic particle carries a negative electrical charge?
a. A neutron
b. A proton
c. An electron
d. A nucleon
ANS: C
A neutron does not carry an electrical charge. A proton carries a positive electrical charge.
An electron carries a negative electrical charge. A nucleon carries a positive (proton) or
,no (neutron) electrical charge.
DIF: Comprehension REF: Page 8 OBJ: 2
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
4. Which of the following elements is the simplest atom?
a. Hydrogen (H #1)
b. Helium (He #2)
c. Nitrogen (N #7)
d. Oxygen (O #8)
ANS: A
Atomic numbers are assigned from simplest to most complex. Hydrogen is the simplest
atom; with a single proton, it has an atomic number of 1. Helium has an atomic number
of 2. Nitrogen has an atomic number of 7. Oxygen has an atomic number of 8.
DIF: Comprehension REF: Page 8 OBJ: 2
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
5. Which of the following statements is true of orbits or shells in the atom?
a. Protons travel around the nucleus in well-
defined shells.
b. An atom contains innumerable shells.
c. The energy level within each shell is the
same.
d. The orbiting shell closest to the nucleus
has the highest energy level.
ANS: D
Electrons travel around the nucleus in well-defined shells. An atom contains a maximum
of seven shells. Each of the maximum seven shells within an atom represents a different
energy level. The orbiting shell closest to the nucleus has the highest energy level. The K
shell is the orbiting shell closest to the nucleus.
DIF: Comprehension REF: Page 8 OBJ: 2
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
6. The binding energy or binding force of an electron is
a. determined by the distance between the
neutrons and protons within the nucleus.
b. determined by the distance between the
orbiting electrons and the nucleus.
c. weaker for electrons located in inner
shells than in outer shells.
d. determined by the atomic number.
, a. determined by the distance between the
neutrons and protons within the nucleus.
b. determined by the distance between the
orbiting electrons and the nucleus.
c. weaker for electrons located in inner
shells than in outer shells.
d. determined by the atomic number.
ANS: B
The binding energy or binding force of an electron is determined by the distance between
the nucleus and the orbiting electron. The binding energy or binding force of an electron
is determined by the distance between the orbiting electron and the nucleus, not the
distance between the orbiting electrons. The binding energy or binding force of an
electron is stronger for electrons located in inner shells than for outer shells.
DIF: Recall REF: Page 8 OBJ: 2 TOP: CDA, N/A
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
7. Which of the following statements is true of ionization?
a. An atom that gains an electron will have a
negative charge.
b. An atom that loses an electron will have a
negative charge.
c. An atom that loses an electron will have a
positive charge.
d. An atom that gains an electron has a
negative charge, and an atom that loses an
electron has a positive charge.
ANS: D
This answer is not the best answer. An atom that gains an electron has a negative charge;
however, an atom that loses an electron has a positive charge. An atom that loses an
electron will have a positive charge. An atom that loses an electron has a positive charge;
however, an atom that gains an electron has a negative charge. An atom that gains an
electron will have a negative charge, and an atom that loses an electron will have a
positive charge.
DIF: Comprehension REF: Page 10 OBJ: 3
TOP: CDA, N/A
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
8. An ion pair results when
a. a proton is removed from an atom.
b. an electron is removed from an atom.
c. a neutron is removed from an atom.
d. two atoms share a pair of electrons.
ANS: B
An ion pair results when an electron is removed from an atom rather than a proton; a
neutron.
, DIF: Recall REF: Page 10 OBJ: 3
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
9. (1) Radiation is the emission and propagation of energy through space or a
substance in the form of waves or particles. (2) Radioactivity can be defined as the
process by which certain unstable atoms or elements undergo spontaneous disintegration,
or decay, in an effort to attain a more balanced nuclear state.
a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second
statement is false.
d. The first statement is false; the second
statement is true.
ANS: A
Radiation is the emission and propagation of energy through space or a substance in the
form of waves or particles. Radioactivity can be defined as the process by which certain
unstable atoms or elements undergo spontaneous disintegration, or decay, in an effort to
attain a more balanced nuclear state.
DIF: Recall REF: Page 10 OBJ: 4
TOP: CDA, RHS, III.B.2. Describe the characteristics of x-radiation
MSC: NBDHE, 2.0 Obtaining and Interpreting Radiographs | NBDHE, 2.1 Principles of
radiophysics and radiobiology
10. The spontaneous emission of radiation from the disintegration of unstable
atomic nuclei is
a. beta particle decay.
b. radiation.
c. radioactivity.
d. alpha particle decay.
ANS: C
Beta particles are fast-moving electrons emitted from the nucleus of radioactive atoms.
Radioactivity is the process by which certain unstable atoms or elements undergo
spontaneous disintegration, or decay, in an effort to attain a more balanced nuclear state.
Radiation is the emission and propagation of energy through space or a substance in the
form of waves or particles. Radioactivity is the process by which certain unstable atoms
or elements undergo spontaneous disintegration, or decay, in an effort to attain a more
balanced nuclear state. Alpha particles are emitted from the nuclei of heavy metals and
exist as two protons and neutrons, without electrons. Radioactivity is the process by
which certain unstable atoms or elements undergo spontaneous disintegration, or decay,
in an effort to attain a more balanced nuclear state.
DIF: Comprehension REF: Page 10 OBJ: 4
