RADR 2209 RADIOGRAPHIC IMAGING
EQUIPMENT EXAM WITH VERIFIED
QUESTIONS AND ANSWERS|| LATEST
VERSION 2026
Section 1: X-Ray Discovery, Characteristics, and Fundamentals
1. Who discovered x-rays, and when and where did this occur?
Wilhelm Conrad Roentgen discovered x-rays on November 8, 1895, in
Wurzburg, Germany.
2. Name five characteristics of x-rays.
X-rays are highly penetrative, travel in straight lines, travel at the speed of light,
can ionize matter, and cannot be focused by a lens.
3. Define ionization.
Ionization is the removal of an electron from an atom.
4. What is an ion pair?
An ion pair is formed when an electron is removed from an atom during the
ionization process.
5. Define velocity.
Velocity is speed in a given direction.
6. Define momentum.
Momentum is the product of an object's mass and velocity.
7. Define work.
Work is force applied over a distance.
8. Define power.
Power is the rate at which work is done.
9. Define inertia.
Inertia is the tendency of an object to resist a change in motion.
,10. Define energy.
Energy is the ability to do work.
11. What is the Roentgen used for, and what is its SI unit?
The Roentgen is used to quantify radiation intensity. Its SI unit is Coulombs per
kilogram (C/kg).
12. What is the Rad used for, and what is its SI unit?
The Rad is used to quantify the absorbed dose (effects) of radiation on people.
Its SI unit is the Gray (Gy).
13. What is the Rem used for, and what is its SI unit?
The Rem quantifies occupational exposure or dose equivalent. Its SI unit is the
Sievert (Sv).
14. What is the Curie used for, and what is its SI unit?
The Curie quantifies radioactive material (not the effects caused by it). Its SI
unit is the Becquerel (Bq).
15. What unit of measure quantifies occupational exposure?
Sievert.
16. Which of the following reflects what a RAD measures?
The biological effects on humans.
17. Which electromagnetic radiation has the ability to ionize matter?
Gamma rays.
18. What is matter?
Anything that occupies space and has mass.
19. What is energy?
Energy is the ability to do work (electric, chemical, thermal, nuclear,
electromagnetic).
20. What is stored energy called?
Potential energy.
21. What is the energy of motion called?
Kinetic energy.
22. What is the motion of atoms called?
Thermal energy (produced by kinetic energy).
23. What is the current, closest model of the atom used?
The Bohr model.
, 24. What are the three fundamental particles of the atom?
The neutron, electron, and proton.
25. What does the atomic nucleus contain?
Protons and neutrons.
26. The earliest atomic theory based on an arrangement similar to the solar
system is attributed to whom?
Rutherford.
27. Who refined Rutherford's work and gave us the theory and model of
the atom we are familiar with?
Niels Bohr.
28. Who was one of the first people to introduce atomic theory?
Leucippus (and his student Democritus) around 400 BC.
29. What was the original name for the atom, and what did it mean?
"Atomos," meaning indivisible.
30. Why is understanding the atom essential to the study of radiologic
science?
Interactions in the x-ray tube that produce x-rays occur at the atomic level, and
interactions that occur at the atomic level determine radiation dose delivered
and radiographic image quality.
31. The interactions in the x-ray tube that produce x-rays occur at which
level?
The atomic level.
32. The nature of the x-ray photon produced depends on how an electron
interacts with what?
The target atom.
33. In radiography, which part of an atom is denser and contains most of
the atom's mass?
The nucleus.
34. What are the outermost electrons called?
Valence electrons (the outermost shell).
35. What is the formula to find the limit of outer-shell electrons?
2n².
36. What is the smallest unit charge in an atom?
The electron.
EQUIPMENT EXAM WITH VERIFIED
QUESTIONS AND ANSWERS|| LATEST
VERSION 2026
Section 1: X-Ray Discovery, Characteristics, and Fundamentals
1. Who discovered x-rays, and when and where did this occur?
Wilhelm Conrad Roentgen discovered x-rays on November 8, 1895, in
Wurzburg, Germany.
2. Name five characteristics of x-rays.
X-rays are highly penetrative, travel in straight lines, travel at the speed of light,
can ionize matter, and cannot be focused by a lens.
3. Define ionization.
Ionization is the removal of an electron from an atom.
4. What is an ion pair?
An ion pair is formed when an electron is removed from an atom during the
ionization process.
5. Define velocity.
Velocity is speed in a given direction.
6. Define momentum.
Momentum is the product of an object's mass and velocity.
7. Define work.
Work is force applied over a distance.
8. Define power.
Power is the rate at which work is done.
9. Define inertia.
Inertia is the tendency of an object to resist a change in motion.
,10. Define energy.
Energy is the ability to do work.
11. What is the Roentgen used for, and what is its SI unit?
The Roentgen is used to quantify radiation intensity. Its SI unit is Coulombs per
kilogram (C/kg).
12. What is the Rad used for, and what is its SI unit?
The Rad is used to quantify the absorbed dose (effects) of radiation on people.
Its SI unit is the Gray (Gy).
13. What is the Rem used for, and what is its SI unit?
The Rem quantifies occupational exposure or dose equivalent. Its SI unit is the
Sievert (Sv).
14. What is the Curie used for, and what is its SI unit?
The Curie quantifies radioactive material (not the effects caused by it). Its SI
unit is the Becquerel (Bq).
15. What unit of measure quantifies occupational exposure?
Sievert.
16. Which of the following reflects what a RAD measures?
The biological effects on humans.
17. Which electromagnetic radiation has the ability to ionize matter?
Gamma rays.
18. What is matter?
Anything that occupies space and has mass.
19. What is energy?
Energy is the ability to do work (electric, chemical, thermal, nuclear,
electromagnetic).
20. What is stored energy called?
Potential energy.
21. What is the energy of motion called?
Kinetic energy.
22. What is the motion of atoms called?
Thermal energy (produced by kinetic energy).
23. What is the current, closest model of the atom used?
The Bohr model.
, 24. What are the three fundamental particles of the atom?
The neutron, electron, and proton.
25. What does the atomic nucleus contain?
Protons and neutrons.
26. The earliest atomic theory based on an arrangement similar to the solar
system is attributed to whom?
Rutherford.
27. Who refined Rutherford's work and gave us the theory and model of
the atom we are familiar with?
Niels Bohr.
28. Who was one of the first people to introduce atomic theory?
Leucippus (and his student Democritus) around 400 BC.
29. What was the original name for the atom, and what did it mean?
"Atomos," meaning indivisible.
30. Why is understanding the atom essential to the study of radiologic
science?
Interactions in the x-ray tube that produce x-rays occur at the atomic level, and
interactions that occur at the atomic level determine radiation dose delivered
and radiographic image quality.
31. The interactions in the x-ray tube that produce x-rays occur at which
level?
The atomic level.
32. The nature of the x-ray photon produced depends on how an electron
interacts with what?
The target atom.
33. In radiography, which part of an atom is denser and contains most of
the atom's mass?
The nucleus.
34. What are the outermost electrons called?
Valence electrons (the outermost shell).
35. What is the formula to find the limit of outer-shell electrons?
2n².
36. What is the smallest unit charge in an atom?
The electron.
