Raphex Exam Newest 2026 Questions and
Correct Detailed Answers Already Graded A+
The first task to perform upon installation of a new linear accelerator is
______________.
a. align lasers with isocenter
b. beam data commissioning
c. shielding survey
d. machine output calibration
e. customer acceptance test - CORRECT ANSWER-c. shielding survey
to ensure the safety of staff during the subsequent acceptance testing and
commissioning
How does one register a diagnostic PET from a combined PET/CT scanner to a
planning CT? - CORRECT ANSWER-Register CT(PET) to CT(plan) and apply
transformation matrix to PET
CBCT imaging _________ QA tests should be performed on a daily basis according
to AAPM TG-142.
a. dose
b. spatial resolution
,c. contrast
d. uniformity and noise
e. alignment of kV and MV beam isocenters - CORRECT ANSWER-e. alignment
of kV and MV beam isocenters
The maximum intensity projection (MIP) acquired in relation to a 4D CT is
________ - CORRECT ANSWER-CT dataset where each individual pixel is
assigned its maximum value from all breathing phases.
The "heel" of a dynamic wedge that employs a moving y-jaw _______ -
CORRECT ANSWER-on the side of the field closest to the start of the moving y-
jaw
The ________ would cease to function properly if a small volume received dose in
excess of its tolerance.
a. parotid
b. kidney
c. lung
d. optic nerve
e. liver - CORRECT ANSWER-d. optic nerve
, In the equation for radioactive decay, lambda represents _________ - CORRECT
ANSWER-the fraction of atoms that decay per unit time
Purpose of rounded leaf ends for MLCs - CORRECT ANSWER-keep the
geometric penumbra relatively constant for different leaf positions
Neutron contamination is greatest in a _______ beam
a. 6 MV photon
b. 10 MV photon
c. 18 MV photon
d. 6 MeV electron
e. 20 MeV electron - CORRECT ANSWER-c. 18 MV photon
remember neutrons are produced through photon interactions, begin happening
above 10 MV photons
Loss of charged particle equilibrium is greatest in lung radiotherapy for field sizes
_______ cm2 and photon energies _______ MV - CORRECT ANSWER-< 5x5; >=
15 MV
effect is greater for higher photon energies since the average energy of the
secondary electrons is greater. effect is greater for small field sizes, harder to
maintain CPE in small space
Correct Detailed Answers Already Graded A+
The first task to perform upon installation of a new linear accelerator is
______________.
a. align lasers with isocenter
b. beam data commissioning
c. shielding survey
d. machine output calibration
e. customer acceptance test - CORRECT ANSWER-c. shielding survey
to ensure the safety of staff during the subsequent acceptance testing and
commissioning
How does one register a diagnostic PET from a combined PET/CT scanner to a
planning CT? - CORRECT ANSWER-Register CT(PET) to CT(plan) and apply
transformation matrix to PET
CBCT imaging _________ QA tests should be performed on a daily basis according
to AAPM TG-142.
a. dose
b. spatial resolution
,c. contrast
d. uniformity and noise
e. alignment of kV and MV beam isocenters - CORRECT ANSWER-e. alignment
of kV and MV beam isocenters
The maximum intensity projection (MIP) acquired in relation to a 4D CT is
________ - CORRECT ANSWER-CT dataset where each individual pixel is
assigned its maximum value from all breathing phases.
The "heel" of a dynamic wedge that employs a moving y-jaw _______ -
CORRECT ANSWER-on the side of the field closest to the start of the moving y-
jaw
The ________ would cease to function properly if a small volume received dose in
excess of its tolerance.
a. parotid
b. kidney
c. lung
d. optic nerve
e. liver - CORRECT ANSWER-d. optic nerve
, In the equation for radioactive decay, lambda represents _________ - CORRECT
ANSWER-the fraction of atoms that decay per unit time
Purpose of rounded leaf ends for MLCs - CORRECT ANSWER-keep the
geometric penumbra relatively constant for different leaf positions
Neutron contamination is greatest in a _______ beam
a. 6 MV photon
b. 10 MV photon
c. 18 MV photon
d. 6 MeV electron
e. 20 MeV electron - CORRECT ANSWER-c. 18 MV photon
remember neutrons are produced through photon interactions, begin happening
above 10 MV photons
Loss of charged particle equilibrium is greatest in lung radiotherapy for field sizes
_______ cm2 and photon energies _______ MV - CORRECT ANSWER-< 5x5; >=
15 MV
effect is greater for higher photon energies since the average energy of the
secondary electrons is greater. effect is greater for small field sizes, harder to
maintain CPE in small space
