Radiology / Radiation Physics Practice Quiz Study

Radiation

Energy carried outward through space or matter by waves or moving particles.

X-Radiation

High-energy, invisible electromagnetic radiation produced when fast-moving electrons collide with a metal target inside an X-ray tube.

X-Ray

A beam of high-energy photon packets that can penetrate substances and record shadow images.

Image Receptor

A recording medium—such as digital sensors or photographic film—used to capture the dental X-ray image.

Atom

The fundamental building block of matter, made up of a central nucleus surrounded by orbiting electrons.

Mass

The amount of matter or weight contained in an object or particle.

Nucleus

The dense, heavy core at the center of an atom.

Proton

A positively charged subatomic particle located inside the atomic nucleus.

Neutron

A neutral (uncharged) subatomic particle located inside the atomic nucleus.

Electron

A tiny, negatively charged subatomic particle that orbits the nucleus.

Electrostatic Force

The physical attraction that keeps negatively charged electrons bound in their orbits around a positively charged nucleus.

Binding Energy

The internal energy holding a specific electron in its orbit around the nucleus (stronger for inner shells).

Ionization

The process where a neutral atom gains or loses an electron, transforming into an unbalanced charged state.

Ion Pair

The resulting split during ionization, consisting of an ejected electron (negative ion) and the remaining atom (positive ion).

Radioactivity

The spontaneous breakdown or decay of unstable atomic nuclei as they try to achieve stability.

Ionizing Radiation

Radiation with enough energy to strip tightly bound electrons from atoms and create ions.

Particulate Radiation

Tiny subatomic particles or atomic nuclei (like alpha and beta particles) traveling at high speeds with mass.

Electromagnetic Radiation

The movement of wavelike energy through space without mass or weight, including light and X-rays.

Electromagnetic Spectrum

The organized range of all electromagnetic wave types, ordered by energy, frequency, and wavelength.

Protons / Quanta

Small, discrete packets of pure electromagnetic energy that travel at the speed of light.

Velocity

The speed of the wave or photon as it travels through space (speed of light for X-rays).

Frequency

The number of complete wave cycles that pass a given point per second (high for X-rays).

Wavelength

The physical distance from the crest of one wave to the crest of the next (short for high-energy X-rays).

Cathode

The negative electrode inside the X-ray tube that contains a tungsten filament to emit electrons via heating.

Anode

The positive electrode containing a tungsten target that stops or slows down high-speed electrons to produce X-ray photons.

What is A. On this Diagram?

Atom

What is B. On the Diagram?

Nucleus

What is C. On the Diagram?

Electron

What is D. On the Diagram?

Proton

What is E. On the Diagram?

Neutron

What is F. On the Diagram?

Shells

What are the three subatomic particles?

1. Electron

2. Proton

3. Neutron

The strongest Binding energy is found in the

K shell

An Atom is considered unbalanced when it

Doesn’t have the same number of protons and electrons

Ionization occurs when an atom loses an

Electron

Radioactivity

The process by which atoms undergo spontaneous decay

Cathode Ray

A stream of high-speed electrons created in the x-ray tube

Radiation

The movement of energy through space in waves and particles

Photon

A bundle of energy created when an electron is removed from the shell or orbit

Frequency

The number of waves that pass a given point

Electromagnetic Radiation: Has Mass / Does not have mass

Does not have mass

Particulate Radiation: Has Mass / Does not have mass

Has Mass

Electromagnetic Radiation: Moves in Waves / Moves in Straight Lines

Moves in Waves

Particulate Radiation: Moves in Waves / Moves in Straight Lines

Moves in Straight Lines

Spontaneous Decay of an atoms subatomic particles is: Radiation / Radioactivity

Radioactivity

A Cathode ray is a form of: Particulate Radiation / Electromagnetic Radiation

Particulate Radiation

Atomic Number

Number of protons

Atomic Weight

Protons + Neutrons

Electrostatic Force

How electrons are maintained in their orbits, exists between protons and neutrons

K-shell

Where the strongest binding energy is found, closest to nucleus

Ion

An atom that gains or loses an electron and becomes unbalanced

Particulate

Possesses mass, travels in straight lines, high speeds

Wavelength

Distance between crests

Insulating Oil

Prevents x-ray tube and transformers from overheating

Collimator

Lead plate with hole that restricts the size/shapes of x-ray as it exists tubehead

Cathode

Negative electrode, consists of tungsten wire filament and molybdenum cup

Molybdenum Cup

Focuses electrons into a narrow beam and directs them toward the tungsten target on the anode

Tungsten Wire Filament

In cathode, coiled wire that generates the electrons needed to produce X-rays

Rectification

Conversion of alternating current (AC) to direct current (DC) within the x-ray machine

Step-down transformer

Decreases incoming 110- or 220-line voltage to the 3 to 6 volts required by the filament circuit

Thermionic Emission

Release of electrons from the tungsten Filament when its heated

General Radiation

70% produced at anode; occurs when electrons hit or pass very close to the tungsten nucleus; NO ionization

Characteristic Radiation

Occurs only at 70KVp and above; requires enough energy to dislodge an inner-shell electron from tungsten atom

Scatter Radiation

When the primary x-ray beam interacts with the patient’s tissues and is deflected from its original path

Photoelectric effect

30%; an x-ray photon is completely absorbed by an inner-shell electron which is ejected as a photoelectron

Compton Scatter

62%; most common interaction; Photon is deflected and loses some energy, ejecting an outer-shell electron