Question 1

Once the NMV has moved away from equilibrium, the following will occur
A) The longitudinal component will increase
B) The transverse component will decrease
C) The longitudinal component will stay the same
D) The transverse component will increase

Accepted Answer

D) The transverse component will increase

Question 2

T2 is the time for the transverse component of the NMV to decrease to what percentage of its maximum value after a 90-degree radio-frequency pulse is applied? A) 33% B) 63% C) 37% D) 67%

Accepted Answer

C) 37%

Question 3

Please provide correct answers along with explanation for these ARMRIT practice questions 1-THE ALIGNMENT OF HYDROGEN ALONG Z AXIS IN
THE PRESENCE OF A STATIC MAGNETIC FIELD CALLED
A-MAGNETIC MOMENTUM
B-GYROMAGNETIC RATIO C-NET MAGNETIC VECTOR
D-LARMOR FREQUENCY

2-NET MAGNETIC VECTOR IN THE ABSENCE OF RF APPLICATION ALIGNED WITH
A-Z AXIS *
B-XY AXIS
C-X AXIS
D-Y AXIS

3-WHICH ELEMENT HAS THE HIGHEST MAGNETIC SUSCEPTIBILITY
A-DIAMAGNETIC
B-PARAMAGNETIC
C-FERROMAGNETIC *
D-COPPER

Magnetic Resonance Imaging is derived from the process known as:
Magnetic resonance
angiography.
A. Magnetic relaxation imaging.
B. Nuclear magnetic resonance*
D) Nuclear resonance imaging.

On a very basic level, the three basic components required to attain MR signals are:
Magnetic field, proton, ionizing radiation.
B) Magnetic field, electron, ionizing radiation.
C) Magnetic field, electron, radio-wave.
D) Magnetic field, proton, radio-wave*.

6) Magnetism can be defined as the ability of certain substances to attract:
Copper, aluminum, tin.
Iron, cobalt, nickel. *
Bronze, niobium, titanium.
Neodymium, niobium-titanium, lodestone.

7-HYDROGEN IS CONSIDERED GREAT
ISOTOP IN MRI BECAUSE
A-HAS A BALANCED NUMBER OF PROTONS
AND ELECTRON
B-HAS AN EVEN NUMBER OF NITRON
C-HAS ODD MASS NUMBER *
D-HAS TWO PROTONS

To represent the flow and area of a magnetic field, lines are used, called:
Gauss.
Axes.
Field or flux. *
Vector.

Magnetic fields have direction, usually designated as north and south. Therefore, magnetic fields are described as:
Vectors
Dipoles. *
Protons.
Axes.
Magnetic fields have strength and direction, which are represented by a:
Field line.
Axis.
Vector.*
Gauss line.

In a loop of conductor in which an electric current is introduced and maintained, a magnetic field will be produced in the center perpendicular to the flow of the electric current. This is called: Damadian’s Law
Gabillard’s Law.
Larmor’s Law.
Faraday’s Law.

12) For very large magnetic fields, such as those employed in MRI systems, the SI unit most commonly used is:
Tesla. *
Gauss.
Kilogauss.
Millitesla.

A 1.5 Tesla magnetic field is equal to:
150 gauss.
1500 gauss.
C) 15,000 gauss.
D) 150.000 gauss.

In the USA, MRI systems in clinical use have main magnetic field strengths that range
from:
A) 2 Tesla to 6 Tesla.
B) 0.06 Tesla to 3 Tesla. *
2 Gauss to 6 Gauss.
0.006 Tesla to 0.03 Tesla.

To describe the uniformity of the MRI system’s main magnetic field, the term employed is:
Stability.
Instability.
Inhomogeneity.
Homogeneity. *

In the USA, the MRI system’s main magnetic field and the vector that represents it are
symbolized:
BI.
B2.
B3.
D) Bo. *

The main magnetic field of MRI systems in clinical use must meet an acceptable
specification of:
A) 10-15 PPM. B) 20-30 PPM. *
C) 40-50 PPM. D) 60-80 PPM.

At any one time, human body tissue is generally composed of 50-90% of what substance?
A) C13
B) NA
C) H2O
D) H *

In MR imaging, for a chemical substance to be affected by the main magnetic field and the radio-wave, it must contain an:
Odd number of electrons*
Odd number of total protons and neutrons.
An even number of total electrons and neutrons.
Even number of protons.

In clinical MR imaging of the human body, the substance of interest is:
H
NA
H2O.

Because of the spinning motion of the hydrogen proton, it has the same properties as a bar magnet. The hydrogen proton’s spinning motion gives it a:
Magnetic charge.
Magnetic spin.
Magnetic moment.
Magnetic
precession.

In MRI, substances respond to a specific radio frequency which is known as:
Magnetic frequency.
Radio frequency.
C) Gyro-magneticfrequency.
D) Resonance frequency. **

The resonance frequency of any substance in a magnetic field can be calculated using the:
Damadian equation.
Larmor equation. *
C) Faraday equation.
D) Lauterbur equation.
All chemical substances have an assigned constant known as the:
Gyro-magnetic ratio. *
Larmor ratio.
Precessional ratio.

Accepted Answer

of hydrogen along the Z-axis in a static magnetic field is called:

✅ C — Net magnetic vector
Why: In B₀, slightly more protons align parallel than antiparallel, creating a net magnetization along Z (longitudinal magnetization / net magnetic vector).

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2) Net magnetic vector in the absence of RF is aligned with:

✅ A — Z axis
Why: Before RF tips anything, magnetization sits longitudinally (along B₀, the Z-axis).

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3) Which has the highest magnetic susceptibility?

✅ C — Ferromagnetic
Why: Ferromagnetic materials (iron, nickel, cobalt, some steels) become strongly magnetized and are the biggest MRI safety risk.

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4) MRI is derived from the process known as:

✅ C — Nuclear magnetic resonance (NMR)
Why: MRI is basically applied NMR, renamed to avoid the scary word “nuclear.”

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5) Three basic components required to attain MR signal:

✅ D — Magnetic field, proton, radio-wave
Why: You need:
• B₀ (static magnetic field),
• MR-active nuclei (in clinical MRI: hydrogen protons),
• RF energy (radiofrequency, non-ionizing).

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6) Magnetism = ability to attract:

✅ Iron, cobalt, nickel
Why: These are the classic ferromagnetic elements.

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7) Hydrogen is the “great” isotope in MRI because:

✅ C — Has odd mass number (best of the choices given)
Why: MR signal requires nonzero nuclear spin, which occurs when there’s an odd number of nucleons (protons+neutrons) → commonly taught as odd mass number.

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8) Lines representing magnetic field flow/area are called:

✅ C — Field or flux (lines)
Why: They’re magnetic flux lines (field lines).

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9) Magnetic fields have north and south → described as:

✅ B — Dipoles
Why: A magnetic field is inherently a dipole field (N/S poles).

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10) Magnetic fields have strength + direction → represented by a:

✅ C — Vector
Why: Anything with magnitude + direction is a vector.

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11) Current in a conductor produces a magnetic field perpendicular to current. This is called:

✅ None of these choices are correct → it’s Ampère’s Law / Right-Hand Rule (Biot–Savart concept)
Why:
• Faraday’s law = changing magnetic field induces voltage (induction).
• The statement given describes magnetic field generated by current, which is Ampère/Biot–Savart + right-hand rule.
So if ARMRIT forces one of the listed answers, the question is badly written—but the correct physics is Ampère/right-hand rule.

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12) SI unit most commonly used for MRI field strength:

✅ A — Tesla
Why: MRI magnets are huge → Tesla is the standard.

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13) 1.5 Tesla equals:

✅ C — 15,000 gauss
Why: 1 Tesla = 10,000 gauss → 1.5T = 15,000G.

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14) US clinical MRI main field strengths range from:

✅ B — 0.06 Tesla to 3 Tesla (classic ARMRIT range)
Why: That’s the standard test range. (Reality now includes more 3T and some 7T, but boards often stick to this.)

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15) Uniformity of the main magnetic field is:

✅ D — Homogeneity
Why: “Uniform” = homogeneous field.

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16) Main magnetic field is symbolized as:

✅ D — B₀ (B-zero)
Why: B₀ is the static main field.

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17) Main magnetic field acceptable specification:

✅ B — 20–30 ppm (as commonly tested)
Why: Homogeneity is often expressed in ppm over a defined imaging volume.

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18) Human tissue is generally 50–90% of what substance?

✅ C — H₂O
Why: The body is mostly water, not pure hydrogen.
So the starred H in your key is wrong.

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19) For a substance to be affected by B₀ and RF, it must contain:

✅ B — Odd number of total protons and neutrons
Why: MR activity requires nonzero nuclear spin → usually occurs with an odd number of nucleons (odd mass number).
Electrons are not the deciding factor for MRI signal.

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20) In clinical MR imaging of the human body, the substance of interest is:

✅ H (hydrogen)
Why: We image mainly hydrogen nuclei (in water + fat) because it’s abundant and gives strong signal.

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21) Proton spinning gives it properties of a bar magnet → it has a:

✅ C — Magnetic moment
Why: Spin creates a magnetic dipole moment (that’s the “tiny bar magnet” idea).

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22) In MRI, substances respond to a specific RF known as:

✅ D — Resonance frequency
Why: Only RF at the correct frequency will efficiently excite spins → resonance.

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23) Resonance frequency in a magnetic field is calculated using:

✅ B — Larmor equation
Why: ω = γB₀ (or f = γB₀ / 2π).

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24) All chemical substances have an assigned constant known as:

✅ A — Gyromagnetic ratio (γ)
Why: γ is nucleus-specific and links field strength ↔ resonance frequency.

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If you want, I can turn these into a clean answer key you can paste into your notes and flag which ones in your starred key are wrong (there are at least #11 and #18–19 issues).

Question 4

To represent the flow and area of a magnetic field, lines are used, called: C — Field or flux (lines)

Accepted Answer

C — Field or flux (lines)

Question 5

Keyhole K-space filling is common employed in dynamic angiography and other applications requiring detailed observations of temporal changes True False

Accepted Answer

True

Question 6

HYDROGEN IS CONSIDERED A GREAT ISOTOPE IN MRI BECAUSE A-HAS BALANCED NUMBER OF PROTON AND ELECTRON B-HAS EVEN NUMBER OF NITRON C-HAS ODD MASS NUMBER D-HAS TWO PROTONS

Accepted Answer

C-HAS ODD MASS NUMBER

Question 7

On a very basic level, the three basic components required to attain MR signals are:
A) Magnetic field, proton, ionizing radiation
B) Magnetic field, electron, ionizing
radiation.
C) Magnetic field, electron, radio-wave.
D) Magnetic field, proton,
radio-wave.

Accepted Answer

D) Magnetic field, proton, radio-wave.

Question 8

Magnetism can be defined as the ability of certain substances to attract: A) Copper, aluminum, tin. B) Iron, cobalt, nickel. C) Bronze, niobium, titanium. D) Neodymium, niobium-titanium, lodestone.

Accepted Answer

B) Iron, cobalt, nickel.

Question 9

As the TE _______, TOF effects_______. Increases / increase Increases / decrease No answers are correct Decreases / increase

Accepted Answer

Increases / decrease Short TE = stronger inflow effect Long TE = weaker inflow effect

Physics1 Flashcards

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