Deck 2: Radiation Physics

Question 1

Which of the following types of particulate radiation are emitted from the nucleus of radioactive atoms?

A) Alpha particles
B) Beta particles
C) Protons
D) Neutrons

Answer 1

Beta particles

Question 2

Photons are:

A) Bundles of energy with mass and weight.
B) Bundles of energy that travel at the speed of sound.
C) A component of the particle concept of electromagnetic radiation.
D) A component of the wave concept of electromagnetic radiation.

Answer 2

A component of the particle concept of electromagnetic radiation.

Question 3

Which of the following statements is/are true of ionizing radiation?

A) It is radiation that is capable of producing ions by removing or adding an electron to an atom.
B) It is strictly an electromagnetic radiation and does not involve particles that have mass.
C) It may be classified as to whether it is particulate or electromagnetic radiation.
D) Both a and c.

Answer 3

Both a and c.

Question 4

Particulate radiations:

A) Are tiny particles of matter.
B) Do not possess mass.
C) Travel in curved lines at low speeds.
D) Do not transmit kinetic energy.

Question 5

Cathode rays are derived from which of the following types of particulate radiation?

A) Electrons
B) Alpha particles
C) Protons
D) Neutrons

Question 6

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.

Question 7

Which of the following statements is/are 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) Both a and c.

Question 8

Which component of the x-ray tubehead absorbs heat created by the production of x-rays?

A) Metal housing
B) Insulating oil
C) Aluminum discs
D) Lead collimator

Question 9

Which of the following components of the x-ray machine would have an indicator light for the on-off switch and an indicator light for the exposure button?

A) X-ray tube
B) X-ray tubehead
C) The control panel
D) The extension arm

Question 10

Electromagnetic radiations:

A) Are entirely man-made.
B) Include x-rays and visible light.
C) Are a form of particulate radiation.
D) Have mass.

Question 11

The fundamental unit of matter is the:

A) Proton
B) Neutron
C) Electron
D) Atom

Question 12

Which of the following statements is true of the wave concept of electromagnetic radiation?

A) Wavelength refers to the speed of the wave.
B) Velocity refers to the number of wavelengths that pass a given point in a certain amount of time.
C) Frequency is defined as the distance between the crest of one wave and the crest of the next.
D) Frequency and wavelength are inversely related.

Question 13

Which subatomic particle carries a negative electrical charge?

A) Neutron
B) Proton
C) Electron
D) Nucleon

Question 14

Radioactivity is:

A) The emission and propagation of energy through space or a substance in the form of waves.
B) The emission and propagation of energy through space or a substance in the form of particles.
C) The process by which certain unstable atoms or elements undergo spontaneous disintegration, or decay, in an effort to attain a more balanced nuclear state.
D) The process by which certain unstable atoms or elements undergo spontaneous disintegration, or decay, in an effort to attain a less balanced nuclear state.

Question 15

The nucleus of an atom contains:

A) Protons
B) Neutrons
C) Protons and neutrons
D) Electrons

Question 16

Which of the following forms of electromagnetic radiation are capable of ionization?

A) Radio waves
B) Visible light
C) Ultraviolet light
D) X-rays

Question 17

Which of the following elements is the simplest atom, with an atomic number of 1?

A) Hydrogen
B) Helium
C) Nitrogen
D) Oxygen

Question 18

Which of the following forms of electromagnetic radiation has the shortest wavelength?

A) Radio wave
B) Television wave
C) Radar wave
D) Dental x-ray wave

Question 19

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 K shell is located closest to the nucleus and has the highest energy level.

Question 20

The binding energy or binding force of an electron is:

A) Determined by the distance between the neutrons and protons within the nucleus.
B) Weaker for electrons located in outer shells than for inner shells.
C) Weaker for electrons located in inner shells than for outer shells.
D) Both a and c.

Question 21

Thermionic emission of electrons occurs at the:

A) Tungsten filament in the anode.
B) Tungsten filament in the cathode.
C) Copper stem.
D) Molybdenum cup.

Question 22

Which of the following four possibilities that can occur when an x-ray photon interacts with matter is responsible for producing densities on film that make dental radiography possible?

A) No interaction
B) Absorption or photoelectric effect
C) Compton scatter
D) Coherent scatter

Question 23

The purpose of the anode is to:

A) Produce electrons when heated.
B) Convert electrons into x-ray photons.
C) Absorb heat created by the production of x-rays.
D) Filter out nonpenetrating, longer-wavelength x-rays.

Question 24

Which transformer in the x-ray machine is used to increase the voltage from the incoming 110- or 220-line voltage to the 65,000 to 100,000 volts required?

A) Step-down transformer
B) Step-up transformer
C) Autotransformer
D) Both a and c

Question 25

Within the x-ray tube, electrons are generated by the:

A) Tungsten filament in the cathode.
B) Tungsten filament in the anode.
C) Molybdenum cup.
D) Copper stem.

Question 26

Which of the following statements is true of general radiation?

A) It is also known as braking (bremsstrahlung) radiation.
B) It is also known as characteristic radiation.
C) It is the source of the majority of x-rays that are produced.
D) Both a and c.

Question 27

Which is the most common possibility when an x-ray photon interacts with matter?

A) No interaction
B) Absorption or photoelectric effect
C) Compton scatter
D) Coherent scatter

Question 28

Approximately what percentage of the kinetic energy of the electrons is converted to x-rays at the anode?

A) Less than 1%
B) 25%
C) 50%
D) 100%

Question 29

Which form of the x-ray beam is most detrimental to the patient and operator?

A) Primary radiation
B) Secondary radiation
C) Scatter radiation
D) Useful beam

Question 30

Which component of the tubehead aims and shapes the x-ray beam?

A) Metal housing
B) Tubehead seal
C) Aluminum discs
D) Position-indicating device

Question 31

____ is the measurement of the number of electrons moving through a conductor.

A) Alternating current
B) Direct current
C) Amperage
D) Voltage

Question 32

The lead collimator:

A) Carries away the heat produced during the production of x-rays.
B) Permits a small number of x-rays to exit from the x-ray tube.
C) Filters the longer-wavelength x-rays from the beam.
D) Restricts the size of the x-ray beam.