Chapter 01
1. Which of the following is a vector? [Multiple Choice]
a. Distance
b. A magnetic field’s strength and direction ✔
c. Your height
d. Time
e. The purity of a bar of soap
ANS: B
A vector has both magnitude and direction; b is the only choice that has both.
2. In the presence of a strong magnetic field, what does a proton do? [Multiple Choice]
a. Precess ✔
b. Nothing
c. Flip
d. Collapse
e. Emit radiation
ANS: A
Protons will begin to precess in the presence of a magnetic field.
3. What is the gyromagnetic ratio of hydrogen? [Multiple Choice]
a. 42.6 MHz/T ✔
b. 40.1 MHz/T
c. 17.2 MHz/T
d. 11.3 MHz/T
e. 10.7 MHz/T
ANS: A
The gyromagnetic ration of hydrogen is 42.6 MHz/T.
,4. Which of the following terms describes how well an imaging system can detect subtle differences in anatomy?
[Multiple Choice]
a. Sensitivity ✔
b. Specificity
c. Contrast
d. Resolution
e. Dose
ANS: A
Sensitivity is, by definition, the term that describes how well an imaging system detects differences in anatomy.
5. What does the Larmor equation tell us? [Multiple Choice]
a. Dose from MRI
b. Precessional frequency ✔
c. How many RF pulses we need
d. Gradient strength
e. Speed of the patient
ANS: B
From the Larmor equation, we can determine the precessional frequency of a proton.
6. What is the orientation of the magnetization of hydrogen protons under normal conditions in the human body?
[Multiple Choice]
a. North
b. South
c. East
d. Random ✔
e. Aligned
ANS: D
When the human body is not exposed to a strong magnetic field, the protons in the body are randomly aligned,
and there is no net magnetization.
7. Which of the following terms describes the ability of an imaging system to precisely identify the nature of
,differences in anatomy? [Multiple Choice]
a. Sensitivity
b. Specificity ✔
c. Contrast
d. Resolution
e. Dose
ANS: B
Specificity is, by definition, the term that describes how well an imaging system identifies the nature of
differences in anatomy.
8. The large arrow denoted by MZ symbolizes what? [Multiple Choice]
a. Magnetic field strength
b. RF pulse strength
c. Net magnetization of the protons ✔
d. Net magnetization of the electrons
e. Direction of motion
ANS: C
When talking about MRI physics, we use the variable MZ to designate the net magnetization of protons in the
magnetic field.
9. All electromagnetic radiation travels at what speed? [Multiple Choice]
a. Speed of light ✔
b. Speed of sound
c. 70 mph
d. Depends on the medium it travels in
e. 2× the speed of light
ANS: A
A property of electromagnetic radiation is that it travels at the speed of light.
10. Which of the following is not related to MRI? [Multiple Choice]
, a. T1 relaxation
b. kVp ✔
c. T2 relaxation
d. Proton density
e. RF pulse
ANS: B
kVp is a property used in x-ray imaging.
11. MRI operates in the same electromagnetic energy range as _______________. [Multiple Choice]
a. x-rays
b. visible light
c. gamma rays
d. microwaves
e. radiowaves ✔
ANS: E
The RF pulses in MRI have an energy in the range of radiowaves.
12. Which of the following is not a component of an MRI scanner? [Multiple Choice]
a. Computer
b. Collimator ✔
c. Magnet
d. RF coil
e. Gradient coil
ANS: B
A collimator is used in x-ray imaging, not in MRI.
13. What is the orientation of magnetization of hydrogen protons in the human body when it is placed in a strong
magnetic field (B0)? [Multiple Choice]
a. North
1. Which of the following is a vector? [Multiple Choice]
a. Distance
b. A magnetic field’s strength and direction ✔
c. Your height
d. Time
e. The purity of a bar of soap
ANS: B
A vector has both magnitude and direction; b is the only choice that has both.
2. In the presence of a strong magnetic field, what does a proton do? [Multiple Choice]
a. Precess ✔
b. Nothing
c. Flip
d. Collapse
e. Emit radiation
ANS: A
Protons will begin to precess in the presence of a magnetic field.
3. What is the gyromagnetic ratio of hydrogen? [Multiple Choice]
a. 42.6 MHz/T ✔
b. 40.1 MHz/T
c. 17.2 MHz/T
d. 11.3 MHz/T
e. 10.7 MHz/T
ANS: A
The gyromagnetic ration of hydrogen is 42.6 MHz/T.
,4. Which of the following terms describes how well an imaging system can detect subtle differences in anatomy?
[Multiple Choice]
a. Sensitivity ✔
b. Specificity
c. Contrast
d. Resolution
e. Dose
ANS: A
Sensitivity is, by definition, the term that describes how well an imaging system detects differences in anatomy.
5. What does the Larmor equation tell us? [Multiple Choice]
a. Dose from MRI
b. Precessional frequency ✔
c. How many RF pulses we need
d. Gradient strength
e. Speed of the patient
ANS: B
From the Larmor equation, we can determine the precessional frequency of a proton.
6. What is the orientation of the magnetization of hydrogen protons under normal conditions in the human body?
[Multiple Choice]
a. North
b. South
c. East
d. Random ✔
e. Aligned
ANS: D
When the human body is not exposed to a strong magnetic field, the protons in the body are randomly aligned,
and there is no net magnetization.
7. Which of the following terms describes the ability of an imaging system to precisely identify the nature of
,differences in anatomy? [Multiple Choice]
a. Sensitivity
b. Specificity ✔
c. Contrast
d. Resolution
e. Dose
ANS: B
Specificity is, by definition, the term that describes how well an imaging system identifies the nature of
differences in anatomy.
8. The large arrow denoted by MZ symbolizes what? [Multiple Choice]
a. Magnetic field strength
b. RF pulse strength
c. Net magnetization of the protons ✔
d. Net magnetization of the electrons
e. Direction of motion
ANS: C
When talking about MRI physics, we use the variable MZ to designate the net magnetization of protons in the
magnetic field.
9. All electromagnetic radiation travels at what speed? [Multiple Choice]
a. Speed of light ✔
b. Speed of sound
c. 70 mph
d. Depends on the medium it travels in
e. 2× the speed of light
ANS: A
A property of electromagnetic radiation is that it travels at the speed of light.
10. Which of the following is not related to MRI? [Multiple Choice]
, a. T1 relaxation
b. kVp ✔
c. T2 relaxation
d. Proton density
e. RF pulse
ANS: B
kVp is a property used in x-ray imaging.
11. MRI operates in the same electromagnetic energy range as _______________. [Multiple Choice]
a. x-rays
b. visible light
c. gamma rays
d. microwaves
e. radiowaves ✔
ANS: E
The RF pulses in MRI have an energy in the range of radiowaves.
12. Which of the following is not a component of an MRI scanner? [Multiple Choice]
a. Computer
b. Collimator ✔
c. Magnet
d. RF coil
e. Gradient coil
ANS: B
A collimator is used in x-ray imaging, not in MRI.
13. What is the orientation of magnetization of hydrogen protons in the human body when it is placed in a strong
magnetic field (B0)? [Multiple Choice]
a. North
