MDCB Practice Set 1 - Test 2 Exam
Questions With 100% Verified Answers
The development of which of the following conditions is an
example of a stochastic effect of
radiation?
A. organ atrophy
B. second primary
C. pulmonary fibrosis
D. decreased sperm count -
correct answer ✅B
2. When an enface electron beam is used for chest wall irradiation,
which of the following
describes the dose at the interface between the chest wall and
lung?
A. decreased due to reduced scatter from the lung
B. decreased due to irregular surface contour effects
C. increased due to an increase in the electron fluence
D. increased due to a larger angle of electron scatter -
correct answer ✅A
3. An averaged ionization chamber reading for a 10 cm x 10 cm
electron applicator is 98.5
,MDCB Practice Set 1 - Test 2 Exam
Questions With 100% Verified Answers
and an averaged ionization chamber reading for an electron cut-out
in a 6 cm x 10 cm
applicator is 92.4. What is the monitor unit setting if 200 cGy is
prescribed to 90% and the 6 cm
x 10 cm cut-out is utilized? (The output factor for 10 cm x 10 cm is 1
cGy/MU.)
A. 208 MU
B. 217 MU
C. 222 MU
D. 237 MU -
correct answer ✅D
4. Parent and daughter radioactive isotopes are said to be in secular
equilibrium when they:
A. are equal in atomic weight.
B. have the same half-life.
C. have a constant ratio of activity.
D. emit equivalent gamma energies. -
correct answer ✅C
, MDCB Practice Set 1 - Test 2 Exam
Questions With 100% Verified Answers
5. To make inhomogeneity corrections in treatment plans based on
CT derived anatomical
information, the TPS:
A. converts CT numbers to Hounsfield units.
B. determines the absorption equivalents.
C. converts to equivalent path lengths.
D. determines electron densities. -
correct answer ✅D
6. When opposing lateral fields to the pharynx are abutted at
midline to an anterior field to the supraclavicular fossae, overdose
in the cord may be avoided by:
A. a 0.5 cm wide by 0.5 cm long midline block placed in the
superior portion of the
anterior field.
B. a small block over the cord in the inferior posterior corner of
both lateral fields.
C. angling the laterals fields off the cord.
D. angling the supraclavicular field off the cord. -
correct answer ✅B
Questions With 100% Verified Answers
The development of which of the following conditions is an
example of a stochastic effect of
radiation?
A. organ atrophy
B. second primary
C. pulmonary fibrosis
D. decreased sperm count -
correct answer ✅B
2. When an enface electron beam is used for chest wall irradiation,
which of the following
describes the dose at the interface between the chest wall and
lung?
A. decreased due to reduced scatter from the lung
B. decreased due to irregular surface contour effects
C. increased due to an increase in the electron fluence
D. increased due to a larger angle of electron scatter -
correct answer ✅A
3. An averaged ionization chamber reading for a 10 cm x 10 cm
electron applicator is 98.5
,MDCB Practice Set 1 - Test 2 Exam
Questions With 100% Verified Answers
and an averaged ionization chamber reading for an electron cut-out
in a 6 cm x 10 cm
applicator is 92.4. What is the monitor unit setting if 200 cGy is
prescribed to 90% and the 6 cm
x 10 cm cut-out is utilized? (The output factor for 10 cm x 10 cm is 1
cGy/MU.)
A. 208 MU
B. 217 MU
C. 222 MU
D. 237 MU -
correct answer ✅D
4. Parent and daughter radioactive isotopes are said to be in secular
equilibrium when they:
A. are equal in atomic weight.
B. have the same half-life.
C. have a constant ratio of activity.
D. emit equivalent gamma energies. -
correct answer ✅C
, MDCB Practice Set 1 - Test 2 Exam
Questions With 100% Verified Answers
5. To make inhomogeneity corrections in treatment plans based on
CT derived anatomical
information, the TPS:
A. converts CT numbers to Hounsfield units.
B. determines the absorption equivalents.
C. converts to equivalent path lengths.
D. determines electron densities. -
correct answer ✅D
6. When opposing lateral fields to the pharynx are abutted at
midline to an anterior field to the supraclavicular fossae, overdose
in the cord may be avoided by:
A. a 0.5 cm wide by 0.5 cm long midline block placed in the
superior portion of the
anterior field.
B. a small block over the cord in the inferior posterior corner of
both lateral fields.
C. angling the laterals fields off the cord.
D. angling the supraclavicular field off the cord. -
correct answer ✅B
