Part
1: Physics of Nuclear Medicine
Atomic
Structure, Radioactive Decay, Interaction of Ionizing Radiation with Matter
1.
An atomic nucleus contains 39 protons and 50 neutrons. Its mass number
(A) is
a)
39
b)
50
c)
11
d)
89
e)
None of the above
2. In
standard notation, one of the isotopes of bromine is Br73
35
How many neutrons does this nucleus
contain?
a)
38
b)
73
c)
35
d)
108
3. The
fundamental particles of greatest interest in the physics of nuclear medicine
are the proton, the neutron, and the electron. Of these
a)
the electron is the least massive and has negative charge
b)
the proton is the least massive and has negative charge
c)
the proton is the least massive and has positive charge
d)
the neutron is the most massive and has positive charge
4. A parent
nucleus decays by emitting a gamma photon. Parent and daughter nuclei are:
a)
isotopes
b)
isotones
c)
isobars
d)
isomers
e)
combination of 2 or more of the above
238
5.
Consider the isotope
U
92
. What is
_____ a) number of protons
_____ b) number of neutrons
_____ c) number of electrons
_____ d) number of nucleons
_____ f) an
Isotope of Uranium-238
_____ g) an Isotone of
Uranium-238
_____ h) an Isobar of
Uranium-238
6. In b—
-decay, which of the following is emitted?
a)
an ordinary electron
b)
a positron
c)
a positron/electron pair
d)
annihilation radiation
7. The principal types
of radiation listed by descending mass are:
b)
b,a,g
c)
a,g,b
d)
a,b,g
8. Which of the
following represents the ranking, in increasing order of range in air,
of a, b, and g rays?
a)
a,b,g
b)
b,g,a
c)
g,b,a
d)
none of the above
9. For an unknown isotope X mark each of the following statements True
or False.
a)
The Z number represents the number of electrons
b)
The Z number represents the number of protons
c)
The neutrons are represented by (Z-A)
d)
Electrons in outer orbitals are electrically balanced by positrons in
the nucleus
e)
The mass number A = (2Z + N)
10.
Gamma rays are most similar to which one of the following
a)
X-rays
b)
high speed electrons
c)
infra-red radiation
d)
sound waves
e)
laser beams
11.
Answer true or false to these statements regarding Tc-99m
a)
The tphys is affected by gravity and heat, but no other
environmental factors.
b)
The predominant gamma ray energy is 140 KeV.
c)
Technetium isotopes are synthetic; none occur naturally.
d)
Tc-99m differs from Tc-99g in terms of photon energy, mode
of decay, and tphys.
12.
Which of the following lists consists of nuclei that are ISOTONES?
a)
I131 Xe131
Te131
Sb131
53 54
52
51
b)
I131 Xe132
Te130
Sb129
53
54
52
51
c)
Cs129 Xe129
I129
55
54
53
d)
a and c
U238
(3n,2p) ________
92
a)
92, 239
b)
90, 239
c)
92, 238
d)
90, 238
b)
It will decay by emitting an alpha particle immediately after it is
formed
c)
It will decay by emitting a gamma photon some measurable time after it
is formed.
d)
It will not undergo radioactive decay.
15.
The decay of Tc-99m to Tc-99g is an example of:
b)
neutrino production
c)
isomeric transition
d)
photoelectric effect
e)
none of the above.
16.
After an atom has decayed by giving off a negative beta particle and a
gamma ray, the remaining atom is:
a)
An atom of a new element having an atomic number one higher than the
old and with no or little change in mass number.
b)
An atom of a new element having an atomic number one higher than the
old and with a significant lowering of mass number.
c)
Unchanged except it has now become stable.
d)
An atom of a new element having an atomic number one less than the old
and with no or little change in mass number.
17.
Internal conversion is most similar diagrammatically to:
a)
isomeric transition
b)
compton effect
c)
pair production
d)
photoelectric effect
18.
The formula Ee - = Eg
- BE describes which of the following interactions with matter?
a)
compton effect
b)
photoelectric effect
c)
pair production
d)
isomeric transition
e)
none of the above
19.
Pair production takes place
a)
only in presence of nuclei
b)
only in a vacuum
c)
only in solids
d)
none of the above
20.
The literature value for the b-
energy of Ca45 is 0.255 MeV. This represents
a)
the mean energy
b)
the median energy
c)
the maximum energy
d)
the root mean square energy
21.
In b—
emission, the total decay energy is shared between the b— particle and
a)
a neutron
b)
a neutrino
c)
a b+
-particle
d)
there is no sharing involved
22.
Answer True/False to the following statements regarding b+
- emitters.
a)
Positrons are imaged following their interaction in a sodium iodide
crystal
b)
b+
- emitting nuclides have previously undergone pair production
c)
When a b+ at
its rest mass interacts with matter, it loses its energy by photoelectric and
Compton effects
d)
The process that competes with b+ emission is called isomeric
transition
23.
In a-decay which of the following takes place?
a)
The Z number of the daughter is 2 greater than of the parent
b)
The A number of the daughter is 2 greater than of the parent
c)
The Z number of the daughter is 2 less than of the parent
d)
The A number of the daughter is 2 less than of the parent
e)
c and d
24.
Which of the following processes occurs spontaneously in an effort to
reduce the N/P ratio?
a)
b-
emission
b)
b+
emission
c)
a2+
emission
d)
a2-
emission
25. Refer to the diagram at right and match the mode of
decay with the appropriate line in the composite decay scheme:
a.
b
minus ______
Line PA
b.
b
plus ______
Line PB
c.
EC
______
Line PXC
d.
IT
______
Line PC
e.
a
______
Line PD
26.
Answer True/False to the following statements
a)
In the Compton effect, Eg2
depends upon, Eg1
b)
In the Photoelectric effect, Eg2
depends upon Eg1
c)
Pair production results in e + and an e- emitted
at a 180o angle to each other
d)
A result of the Compton effect is pair production
e)
The 511 KeV positrons in pair production annihilate electrons in matter
27.
Which of the following is/are example(s) of specific activity?
a)
mg/Ci
b)
Ci/mmole
c)
counts/mmole
d)
a and c
e)
b and c
28.
Which of the following accurately defines a millicurie?
a)
3.7 x 107 counts/sec
b)
3.7 x 107 counts/min
c)
3.6 x 107 disintegrations/sec
d)
3.7 x 107 disintegrations/sec
29.
Answer True/False to the following statements
a)
Tc-99m decays by internal conversion to Tc-99g
b)
b+
decay competes with b- decay in many nuclides
c)
Internal conversion electrons emitted from inside an internal organ
lose approximately 10% of their energy in that organ
d)
Tc-99g (t½= 2 x 105 yr) has been
discovered in Siberian mineral deposits.
30.
Characteristic radiation may be produced by the interaction of ________
and matter. (Answer True/False)
a)
Electrons
b)
Protons
c)
Photons
d)
Neutrons
31.
For pair production interactions (Answer True/False)
a)
Electrons and positrons are produced.
b)
The incident photons must have energies greater than or equal to 1.02
MeV.
c)
The total energy of the incident photon is divided between the kinetic
energy of the positron and the electron.
d)
The annihilation of the positron produces 1.02 MeV photons.
e)
The electron and positron are emitted in opposite directions.
32.
For oxygen-15 decay (Answer True/False)
a)
The atomic number (Z) decreases.
b)
A neutrino is emitted.
c)
The mass of the daughter is less than the parent.
d)
0.511 MeV photons are emitted.
33.
As atomic number increases, the number of neutrons in the nucleus
a.
decreases, but mass number increases.
b.
increases the same as the atomic number.
c.
increases, but mass number remains constant.
d.
increases at a somewhat greater rate than the atomic number increase.
e.
remains constant.
34.
Radionuclides decaying by isomeric transition
a.
emit only gamma rays.
b.
emit only characteristic x-rays.
c.
emit only gamma rays and characteristic x-rays.
d.
emit only positrons.
e.
may emit x-rays, gamma rays, conversion electrons and Auger
electrons.
35. 35.
Nuclear transitions involving only a change of energy state are:
a.
called "isomeric" and involve emission of photons.
b.
called "isomeric" and involve emission of beta particles.
c.
called "isomeric" and involve neutron emission.
d.
called “isobaric” and involve electron capture.
36.
Which one of the following is not a likely product of the decay
of a neutron-rich species?
a.
gamma rays
b.
beta-minus particles
c.
characteristic x-rays
d.
Auger electrons
e.
beta-plus particles
37.
Select the answer which has the following radionuclides listed in order
of increasing gamma ray energy.
2.
I-125
3.
I-131
4.
Tc-99m
5.
Cs-137
a.
1,2,3,4,5
b.
1,2,4,3,5
c.
2,1,4,3,5
d.
2,1,4,5,3
e.
2,4,1,3,5
1.
Internal conversion
2.
isomeric transitions
3.
compton interactions
4.
electron capture
5.
photoelectric interactions
a.
1,2,3,5
b.
1,3,5
c.
3,4,5
d.
1,3,4,5
e.
1,2,3,4,5
39.
The energy equivalent of the rest mass of the electron is:
a.
511 keV
b.
81 keV
c.
1.022 MeV
d.
364 keV
b.
collimator
c.
sodium iodide detector
d.
Geiger Muller detector
a.
1,5
b.
1,4
c.
2,3
d.
2,4
e.
3,4
41.
Radiations emitted by a radioactive source decaying by electron capture
may include:
1.
Beta particles
2.
Gamma rays
3.
Conversion electrons
4.
x-rays
5.
Auger electrons
a.
1,2,3,4
b.
1,2,4,5
c.
1,3,4,5
d.
1,2,3,5
e.
2,3,4,5
|
|
42
The FWHM energy resolution of the detector which
produced
the pulse height spectrum at right is
a.
6.3%
b.
8.5%
c.
9.5%
d.
10.6%
