RADIATION THERAPY ESSENTIALS -
MOCK EXAM
Regarding linear accelerators, which of the following is TRUE?
A. Maximum photon energy is equal to the energy of the electron striking the target
B. The bending magnet is rotated out of the beam in the electron mode
C. The beam current is higher in the electron mode than in the photon mode
D. The scattering foil is the primary component for photon production. - Correct Answers
-A. Maximum photon energy is equal to the energy of the electron striking the target
1 mSv is equal to ________ rem.
A. 0.01
B. 0.1
C. 1.0
D. 10 - Correct Answers -B. 0.1
If the total body is exposed to a dose of 4500 cGy in a single exposure, the most likely
cause of death would be:
A. Infection and low blood counts
B. Severe damage to the intestines
C. Cerebral edema
D. Death would not be likely with this dose - Correct Answers -C. Cerebral edema
By what factor does the intensity decrease when someone moves from 10 meters to 20
meters away from a radioactive source?
A. 2
B. 4
C. 10
D. 20 - Correct Answers -B. 4
What is the allowable cumulative exposure for a radiation worker?
A. One rem times the worker's age in years
,B. Five rem times the worker's age in decades
C. 100 rem times the worker's age in years
D. Five rem times the worker's age in decades - Correct Answers -A. One rem times the
worker's age in years
Which of the following are interactions between an incident photon and an atomic
nucleus?
A. Photoelectric
B. Compton
C. Coherent
D. Pair production - Correct Answers -D. Pair production
A barrier that attenuates the useful portion of the beam to the required degree is known
as?
A. Secondary barrier
B. incident shielding
C. tenth value layer
D. Primary barrier - Correct Answers -D. Primary barrier
A "star" shot on a linear accelerator is performed to test the rotational axis of the:
[1] collimator
[2] couch
[3] gantry
A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2, and 3 - Correct Answers -D. 1, 2, and 3
Direct exposure to lasers that are used for patient alignment purposes can be a hazard
for the:
A. Pituitary
B. Retina
C. Commissure
D. Inner Ear - Correct Answers -B. Retina
The average photon beam energy produced by a 6 MV linear accelerator is
approximately _____ MV.
A. 2
B. 4
C. 6
,D. 9 - Correct Answers -A. 2
Which of the following tissues arise from mesenchymal stem cells (MSC)?
[1] blood
[2] cartilage
[3] bone
A. 1 only
B. 2 only
C. 2 and 3
D. 1, 2, and 3 - Correct Answers -D. 1, 2, and 3
In bremsstrahlung radiation, the incoming electron:
A. Interacts with an orbiting electron
B. is deflected by the nucleus of the atom
C. creates a positive and negative ion
D. cascades to a lower energy state - Correct Answers -B. is deflected by the nucleus of
the atom
Exposure is:
A. Measure of ionization in air
B. Known as a biological dose equivalent
C. The absorbed dose multiplied by the quality factor
D. The possibility of a random interaction - Correct Answers -A. Measure of ionization in
air
Which of the following does not ionize directly?
A. Proton
B. Neutron
C. Alpha particle
D. Electron - Correct Answers -B. Neutron
The half-life of cobalt-60 is:
A. 2.5 years
B. 3.2 years
C. 5.3 years
D. 8.2 years - Correct Answers -C. 5.3 years
Linear accelerators have which of the following type of target?
A. Hooded anode
B. Waveguide
, C. Transmission
D. Rotating cathode - Correct Answers -C. Transmission
Klystrons and magnetrons are:
A. Radiation monitors
B. Microwave sources
C. Monitors used for mechanical motions
D. Beam shaping devices - Correct Answers -B. Microwave sources
Which of the following is the most common metastatic site for prostate cancer?
A. Lung
B. Liver
C. Bone
D. Brain - Correct Answers -C. Bone
The last part of the colon that leads into the rectum is known as the:
A. Ascending colon
B. Hepatic colon
C. Descending colon
D. Sigmoid colon - Correct Answers -D. Sigmoid colon
Why do high energy photon accelerators require flattening filters?
A. To increase the penetrating ability of the beam
B. To reduce dose rates to a safe level
C. To filter out low energy photons
D. To decrease the intensity along the central axis - Correct Answers -D. To decrease
the intensity along the central axis
Lead alone could be used in room shielding when the following interactions
predominate:
A. Photoelectric
B. Bragg peak
C. Pair production
D. Compton scattering - Correct Answers -A. Photoelectric
The intensity of a radiation beam is measured at a distance of 100 cm and is found to
be 150 cGy/min. What is the intensity of this beam at 105 cm?
A. 136 cGy/min
B. 143 cGy/min
C. 157 cGy/min
MOCK EXAM
Regarding linear accelerators, which of the following is TRUE?
A. Maximum photon energy is equal to the energy of the electron striking the target
B. The bending magnet is rotated out of the beam in the electron mode
C. The beam current is higher in the electron mode than in the photon mode
D. The scattering foil is the primary component for photon production. - Correct Answers
-A. Maximum photon energy is equal to the energy of the electron striking the target
1 mSv is equal to ________ rem.
A. 0.01
B. 0.1
C. 1.0
D. 10 - Correct Answers -B. 0.1
If the total body is exposed to a dose of 4500 cGy in a single exposure, the most likely
cause of death would be:
A. Infection and low blood counts
B. Severe damage to the intestines
C. Cerebral edema
D. Death would not be likely with this dose - Correct Answers -C. Cerebral edema
By what factor does the intensity decrease when someone moves from 10 meters to 20
meters away from a radioactive source?
A. 2
B. 4
C. 10
D. 20 - Correct Answers -B. 4
What is the allowable cumulative exposure for a radiation worker?
A. One rem times the worker's age in years
,B. Five rem times the worker's age in decades
C. 100 rem times the worker's age in years
D. Five rem times the worker's age in decades - Correct Answers -A. One rem times the
worker's age in years
Which of the following are interactions between an incident photon and an atomic
nucleus?
A. Photoelectric
B. Compton
C. Coherent
D. Pair production - Correct Answers -D. Pair production
A barrier that attenuates the useful portion of the beam to the required degree is known
as?
A. Secondary barrier
B. incident shielding
C. tenth value layer
D. Primary barrier - Correct Answers -D. Primary barrier
A "star" shot on a linear accelerator is performed to test the rotational axis of the:
[1] collimator
[2] couch
[3] gantry
A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2, and 3 - Correct Answers -D. 1, 2, and 3
Direct exposure to lasers that are used for patient alignment purposes can be a hazard
for the:
A. Pituitary
B. Retina
C. Commissure
D. Inner Ear - Correct Answers -B. Retina
The average photon beam energy produced by a 6 MV linear accelerator is
approximately _____ MV.
A. 2
B. 4
C. 6
,D. 9 - Correct Answers -A. 2
Which of the following tissues arise from mesenchymal stem cells (MSC)?
[1] blood
[2] cartilage
[3] bone
A. 1 only
B. 2 only
C. 2 and 3
D. 1, 2, and 3 - Correct Answers -D. 1, 2, and 3
In bremsstrahlung radiation, the incoming electron:
A. Interacts with an orbiting electron
B. is deflected by the nucleus of the atom
C. creates a positive and negative ion
D. cascades to a lower energy state - Correct Answers -B. is deflected by the nucleus of
the atom
Exposure is:
A. Measure of ionization in air
B. Known as a biological dose equivalent
C. The absorbed dose multiplied by the quality factor
D. The possibility of a random interaction - Correct Answers -A. Measure of ionization in
air
Which of the following does not ionize directly?
A. Proton
B. Neutron
C. Alpha particle
D. Electron - Correct Answers -B. Neutron
The half-life of cobalt-60 is:
A. 2.5 years
B. 3.2 years
C. 5.3 years
D. 8.2 years - Correct Answers -C. 5.3 years
Linear accelerators have which of the following type of target?
A. Hooded anode
B. Waveguide
, C. Transmission
D. Rotating cathode - Correct Answers -C. Transmission
Klystrons and magnetrons are:
A. Radiation monitors
B. Microwave sources
C. Monitors used for mechanical motions
D. Beam shaping devices - Correct Answers -B. Microwave sources
Which of the following is the most common metastatic site for prostate cancer?
A. Lung
B. Liver
C. Bone
D. Brain - Correct Answers -C. Bone
The last part of the colon that leads into the rectum is known as the:
A. Ascending colon
B. Hepatic colon
C. Descending colon
D. Sigmoid colon - Correct Answers -D. Sigmoid colon
Why do high energy photon accelerators require flattening filters?
A. To increase the penetrating ability of the beam
B. To reduce dose rates to a safe level
C. To filter out low energy photons
D. To decrease the intensity along the central axis - Correct Answers -D. To decrease
the intensity along the central axis
Lead alone could be used in room shielding when the following interactions
predominate:
A. Photoelectric
B. Bragg peak
C. Pair production
D. Compton scattering - Correct Answers -A. Photoelectric
The intensity of a radiation beam is measured at a distance of 100 cm and is found to
be 150 cGy/min. What is the intensity of this beam at 105 cm?
A. 136 cGy/min
B. 143 cGy/min
C. 157 cGy/min
