INTRODUCTION TO RADIOGRAPHY &
PATIENT CARE - WEEK 1 IMPORTANT
POINTS - RADR 1309 EXAM QUESTIONS
AND ANSWERS. VERIFIED 2026.
Who is credited with the discovery of x-rays? - ANS Wilhelm Roentgen, through the discovery
of x-rays through the crooks tube
When was the discovery of x-rays? - ANS November 8, 1895
What are the requirements for x-ray production? - ANS 1. vacuum (x-ray tube)
2. electron source (filament)
3. target for the electrons (anode)
4. high difference (voltage) between the electron source and the target (opposite charges
attract)
Ionizing Radiation - ANS radiation with a wavelength shorter than 1 nm (10^-9 m), it has
sufficient energy to remove an electron from an atomic orbit
@COPYRIGHT 2026/2027 ALL RIGHTS RESERVED
1
, A photon in the center of the primary beam and perpendicular to the long axis of the x-ray tube
is called: - ANS Central Ray (CR)
Remnant Radiation - ANS x-rays that have passed through the body, its travel pattern is a
continuation of the pattern of the primary beam
Scatter Radiation - ANS radiation scattered or created as a result of the attenuation or the
primary x-ray beam by matter. It travels in all direction and is difficult to control.
Primary Radiation - ANS the x-ray beam that leaves the tube and is not attenuated except by
air. Originates at the tube target and expands in a cone shape beam
What does it mean to detent the x-ray tube? - ANS To facilitate places at standard locations,
special mechanism that tends to stop a moving part in a specific location
What is a collimator? - ANS attached to tube housing and controls size of radiation field
When should a bucky/grid be used? - ANS Used to reduce the effect of scatter radiation on
image quality
What is the benefit of using a bucky/grid? - ANS Prevent scatter radiation from reaching the
IR and producing fog that degrades the image
Exposure time (T) - ANS A measurement of how long the exposure will continue; measured in
seconds, fractions of seconds, or milliseconds. A longer exposure time will produce more
exposure and a darker radiographic image.
@COPYRIGHT 2026/2027 ALL RIGHTS RESERVED
2
PATIENT CARE - WEEK 1 IMPORTANT
POINTS - RADR 1309 EXAM QUESTIONS
AND ANSWERS. VERIFIED 2026.
Who is credited with the discovery of x-rays? - ANS Wilhelm Roentgen, through the discovery
of x-rays through the crooks tube
When was the discovery of x-rays? - ANS November 8, 1895
What are the requirements for x-ray production? - ANS 1. vacuum (x-ray tube)
2. electron source (filament)
3. target for the electrons (anode)
4. high difference (voltage) between the electron source and the target (opposite charges
attract)
Ionizing Radiation - ANS radiation with a wavelength shorter than 1 nm (10^-9 m), it has
sufficient energy to remove an electron from an atomic orbit
@COPYRIGHT 2026/2027 ALL RIGHTS RESERVED
1
, A photon in the center of the primary beam and perpendicular to the long axis of the x-ray tube
is called: - ANS Central Ray (CR)
Remnant Radiation - ANS x-rays that have passed through the body, its travel pattern is a
continuation of the pattern of the primary beam
Scatter Radiation - ANS radiation scattered or created as a result of the attenuation or the
primary x-ray beam by matter. It travels in all direction and is difficult to control.
Primary Radiation - ANS the x-ray beam that leaves the tube and is not attenuated except by
air. Originates at the tube target and expands in a cone shape beam
What does it mean to detent the x-ray tube? - ANS To facilitate places at standard locations,
special mechanism that tends to stop a moving part in a specific location
What is a collimator? - ANS attached to tube housing and controls size of radiation field
When should a bucky/grid be used? - ANS Used to reduce the effect of scatter radiation on
image quality
What is the benefit of using a bucky/grid? - ANS Prevent scatter radiation from reaching the
IR and producing fog that degrades the image
Exposure time (T) - ANS A measurement of how long the exposure will continue; measured in
seconds, fractions of seconds, or milliseconds. A longer exposure time will produce more
exposure and a darker radiographic image.
@COPYRIGHT 2026/2027 ALL RIGHTS RESERVED
2
