RADIOLOGIC SCIENCE FOR TECHNOLOGISTS
PRACTICE TEST 100 QUESTIONS AND ANSWERS
LATEST VERSION ALREADY PASSED 2025-2026
1. Which of the following best describes the relationship between
wavelength and frequency of electromagnetic radiation?
A. Directly proportional
B. Inversely proportional
C. Equal
D. Unrelated
Rationale: As wavelength increases, frequency decreases, making
them inversely proportional.
2. The primary function of the X-ray tube cathode is to:
A. Absorb scattered radiation
B. Produce electrons
C. Convert electrons to photons
D. Collimate the beam
Rationale: The cathode contains the filament, which produces
electrons when heated.
3. What is the main advantage of using a rotating anode over a
stationary anode?
A. Decreased exposure time
B. Lower production of heat
C. Increased heat dissipation
D. Reduced tube current
, Rationale: The rotating anode spreads heat over a larger area,
allowing higher exposures without damage.
4. Which interaction is most responsible for the majority of patient
dose in diagnostic radiology?
A. Compton scattering
B. Photoelectric absorption
C. Pair production
D. Coherent scattering
Rationale: Photoelectric absorption transfers energy to tissues,
producing most of the dose.
5. The SI unit of absorbed dose is:
A. Roentgen
B. Rad
C. Gray
D. Sievert
Rationale: Gray (Gy) is the SI unit for absorbed radiation dose.
6. In radiographic imaging, increasing the kVp will:
A. Increase contrast
B. Increase penetration
C. Decrease scatter
D. Reduce density
Rationale: Higher kVp increases the energy of X-ray photons,
enhancing penetration through tissue.
7. Which of the following will reduce patient exposure the most?
A. Increasing mAs
B. Using a higher kVp with lower mAs
C. Reducing SID
, D. Using a larger field size
Rationale: Increasing kVp and reducing mAs maintains image
quality while reducing dose.
8. The inverse square law is used to determine changes in:
A. Intensity of radiation with distance
B. Tube current
C. Exposure time
D. mAs
Rationale: Radiation intensity varies inversely with the square of
the distance from the source.
9. Filtration in an X-ray tube serves to:
A. Increase tube current
B. Remove low-energy photons
C. Reduce anode heat
D. Focus the beam
Rationale: Filtration removes low-energy photons that contribute
to patient dose without improving image quality.
10. The photoelectric effect occurs when an X-ray photon:
A. Is scattered
B. Ejects an inner-shell electron
C. Passes through tissue unaltered
D. Causes pair production
Rationale: The photon transfers all energy to an inner-shell
electron, which is then ejected.
11. Compton scattering primarily affects:
A. Image fog and occupational dose
B. Contrast resolution
, C. Filtration
D. Spatial resolution
Rationale: Compton scattering redirects photons, producing fog
and increasing occupational exposure.
12. Radiographic contrast is influenced primarily by:
A. mAs
B. kVp
C. SID
D. Focal spot size
Rationale: kVp affects the energy spectrum and the differential
absorption in tissues.
13. The primary purpose of a grid is to:
A. Increase scatter radiation
B. Improve image contrast
C. Reduce tube loading
D. Filter low-energy photons
Rationale: Grids absorb scatter radiation before it reaches the
image receptor, improving contrast.
14. The exposure index (EI) indicates:
A. Amount of radiation reaching the image receptor
B. Patient dose
C. SID
D. Grid ratio
Rationale: EI reflects receptor exposure, not patient dose.
15. The characteristic X-ray spectrum depends on:
A. kVp only
B. mAs only
PRACTICE TEST 100 QUESTIONS AND ANSWERS
LATEST VERSION ALREADY PASSED 2025-2026
1. Which of the following best describes the relationship between
wavelength and frequency of electromagnetic radiation?
A. Directly proportional
B. Inversely proportional
C. Equal
D. Unrelated
Rationale: As wavelength increases, frequency decreases, making
them inversely proportional.
2. The primary function of the X-ray tube cathode is to:
A. Absorb scattered radiation
B. Produce electrons
C. Convert electrons to photons
D. Collimate the beam
Rationale: The cathode contains the filament, which produces
electrons when heated.
3. What is the main advantage of using a rotating anode over a
stationary anode?
A. Decreased exposure time
B. Lower production of heat
C. Increased heat dissipation
D. Reduced tube current
, Rationale: The rotating anode spreads heat over a larger area,
allowing higher exposures without damage.
4. Which interaction is most responsible for the majority of patient
dose in diagnostic radiology?
A. Compton scattering
B. Photoelectric absorption
C. Pair production
D. Coherent scattering
Rationale: Photoelectric absorption transfers energy to tissues,
producing most of the dose.
5. The SI unit of absorbed dose is:
A. Roentgen
B. Rad
C. Gray
D. Sievert
Rationale: Gray (Gy) is the SI unit for absorbed radiation dose.
6. In radiographic imaging, increasing the kVp will:
A. Increase contrast
B. Increase penetration
C. Decrease scatter
D. Reduce density
Rationale: Higher kVp increases the energy of X-ray photons,
enhancing penetration through tissue.
7. Which of the following will reduce patient exposure the most?
A. Increasing mAs
B. Using a higher kVp with lower mAs
C. Reducing SID
, D. Using a larger field size
Rationale: Increasing kVp and reducing mAs maintains image
quality while reducing dose.
8. The inverse square law is used to determine changes in:
A. Intensity of radiation with distance
B. Tube current
C. Exposure time
D. mAs
Rationale: Radiation intensity varies inversely with the square of
the distance from the source.
9. Filtration in an X-ray tube serves to:
A. Increase tube current
B. Remove low-energy photons
C. Reduce anode heat
D. Focus the beam
Rationale: Filtration removes low-energy photons that contribute
to patient dose without improving image quality.
10. The photoelectric effect occurs when an X-ray photon:
A. Is scattered
B. Ejects an inner-shell electron
C. Passes through tissue unaltered
D. Causes pair production
Rationale: The photon transfers all energy to an inner-shell
electron, which is then ejected.
11. Compton scattering primarily affects:
A. Image fog and occupational dose
B. Contrast resolution
, C. Filtration
D. Spatial resolution
Rationale: Compton scattering redirects photons, producing fog
and increasing occupational exposure.
12. Radiographic contrast is influenced primarily by:
A. mAs
B. kVp
C. SID
D. Focal spot size
Rationale: kVp affects the energy spectrum and the differential
absorption in tissues.
13. The primary purpose of a grid is to:
A. Increase scatter radiation
B. Improve image contrast
C. Reduce tube loading
D. Filter low-energy photons
Rationale: Grids absorb scatter radiation before it reaches the
image receptor, improving contrast.
14. The exposure index (EI) indicates:
A. Amount of radiation reaching the image receptor
B. Patient dose
C. SID
D. Grid ratio
Rationale: EI reflects receptor exposure, not patient dose.
15. The characteristic X-ray spectrum depends on:
A. kVp only
B. mAs only
