MDCB Complete Exam Set Questions
and Verified Answers (solutions)
(T/F) In SAD techniques, the beams are weighted at dmax point. -
correct answer ✅False
(T/F) In SAD techniques, the beams are weighted at target center. -
correct answer ✅False
(T/F) Isodose or PDD data can be used directly for a patient, without
any modification. -
correct answer ✅False
(T/F) TAR concept is usually not used with accelerator photon
beams because the dose in free air is not well defined due to
conceptual difficulties -
correct answer ✅True
(T/F) TAR can be measured directly or derived from the PDD data. -
correct answer ✅True
(T/F) In general TAR increases with increase in depth. -
correct answer ✅False
,MDCB Complete Exam Set Questions
and Verified Answers (solutions)
(T/F) At orthovoltage beam quality's (>about 0.5 mm Cu HVL) BSF
increases with an increase in energy. -
correct answer ✅False
(T/F) TAR decreases with increase in field size. -
correct answer ✅False
(T/F) Exit dose calculated using the standard PDD tables would give
the correct exit dose. -
correct answer ✅False
(T/F) The off axis ratio is the dose at any point in a plane
perpendicular to the central axis to that of the dose on the central
axis in that plane. -
correct answer ✅True
(T/F) At a phantom depth of 10 cm, on the central axis, scatter
contribution to the dose is more for an accelerator photon beam
compared to a Co‐60 beam. -
correct answer ✅False
,MDCB Complete Exam Set Questions
and Verified Answers (solutions)
(T/F) At any depth, the scatter contribution to total dose decreases
with increase in incident photon energy -
correct answer ✅True
(T/F) Cross‐beam profile can give information regarding field size,
physical penumbra, beam flatness, and symmetry. -
correct answer ✅True
(T/F) A wedge in motion is known as a dynamic wedge. -
correct answer ✅False
(T/F) The energy fluence of the photons falls according to the
inverse square law of distance with the source position as the
origin. -
correct answer ✅True
(T/F) Photon beams have a finite range in a patient. -
correct answer ✅False
(T/F) In the AAPM TG‐51 protocol, the electron beam quality is
specified by E0 , the mean energy of the electrons incident on the
, MDCB Complete Exam Set Questions
and Verified Answers (solutions)
patient. -
correct answer ✅False
(T/F) The field size dependence of the PDD of an accelerator photon
beam is very much influenced by the electron contamination of the
beam -
correct answer ✅True
(T/F) Scatter generally decreases PDD. -
correct answer ✅False
(T/F) Half blocked tangential breast treatments can be easily
accomplished with independent jaw movements. -
correct answer ✅True
(T/F) One of the advantages of a dynamic wedge over a physical
wedge for treatment is that there is no change in beam quality
across the field size. -
correct answer ✅True
and Verified Answers (solutions)
(T/F) In SAD techniques, the beams are weighted at dmax point. -
correct answer ✅False
(T/F) In SAD techniques, the beams are weighted at target center. -
correct answer ✅False
(T/F) Isodose or PDD data can be used directly for a patient, without
any modification. -
correct answer ✅False
(T/F) TAR concept is usually not used with accelerator photon
beams because the dose in free air is not well defined due to
conceptual difficulties -
correct answer ✅True
(T/F) TAR can be measured directly or derived from the PDD data. -
correct answer ✅True
(T/F) In general TAR increases with increase in depth. -
correct answer ✅False
,MDCB Complete Exam Set Questions
and Verified Answers (solutions)
(T/F) At orthovoltage beam quality's (>about 0.5 mm Cu HVL) BSF
increases with an increase in energy. -
correct answer ✅False
(T/F) TAR decreases with increase in field size. -
correct answer ✅False
(T/F) Exit dose calculated using the standard PDD tables would give
the correct exit dose. -
correct answer ✅False
(T/F) The off axis ratio is the dose at any point in a plane
perpendicular to the central axis to that of the dose on the central
axis in that plane. -
correct answer ✅True
(T/F) At a phantom depth of 10 cm, on the central axis, scatter
contribution to the dose is more for an accelerator photon beam
compared to a Co‐60 beam. -
correct answer ✅False
,MDCB Complete Exam Set Questions
and Verified Answers (solutions)
(T/F) At any depth, the scatter contribution to total dose decreases
with increase in incident photon energy -
correct answer ✅True
(T/F) Cross‐beam profile can give information regarding field size,
physical penumbra, beam flatness, and symmetry. -
correct answer ✅True
(T/F) A wedge in motion is known as a dynamic wedge. -
correct answer ✅False
(T/F) The energy fluence of the photons falls according to the
inverse square law of distance with the source position as the
origin. -
correct answer ✅True
(T/F) Photon beams have a finite range in a patient. -
correct answer ✅False
(T/F) In the AAPM TG‐51 protocol, the electron beam quality is
specified by E0 , the mean energy of the electrons incident on the
, MDCB Complete Exam Set Questions
and Verified Answers (solutions)
patient. -
correct answer ✅False
(T/F) The field size dependence of the PDD of an accelerator photon
beam is very much influenced by the electron contamination of the
beam -
correct answer ✅True
(T/F) Scatter generally decreases PDD. -
correct answer ✅False
(T/F) Half blocked tangential breast treatments can be easily
accomplished with independent jaw movements. -
correct answer ✅True
(T/F) One of the advantages of a dynamic wedge over a physical
wedge for treatment is that there is no change in beam quality
across the field size. -
correct answer ✅True
