Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Z MRI Physics > physics quizzes > Flashcards

physics quizzes Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

When the RF pulse is applied the Net Magnetic Value Vector Flips into the ________plane

A

Transverse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Once the RF pulse is removed Mo realigns to Bo and the created transverse magentization decays.

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The F.I.D. can be defined as. (Select all that apply)

A

A. Signal after the R.F. pulse is removed

B. Primary signal

C. Dephasing Hydrogen Protons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In order for resonance to occur the RF Pulse needs to match the exact precessional Frequency of Hydrogen Atoms

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In the presence of a Magnetic Field a spinning proton

A

Precesses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

This signal is the intial signal recieved after the 90 degree excitation pulse.

A

F.I.D.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Transverse Magnetization decreases after the intial excitation pulse is removed

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When Hydrogen Atoms are termed In Phase it refers to the precessing magnetic moments being

A

On the same point in their Precessional Path

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A moving charged particle induces a magnetic field in a plane parallel to its motion

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A unit of electrical charge is measured in

A

Coulomb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Control of TE is exercised by control of

A

T2 relaxation time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Free Induction decay is ad RF wave that is emitted from the patient

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In order for resonance to occur what has to happen

A

Precessional Frequency and RF pulse must match

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

T1 and T2 times occur at the same time

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

T1 is also termed

A

Longitudinal Relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

T2 is also termed

A

Transverse Relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The Fourier Transform of the FID results in a nuclear magnetic spectrum which is in the frequency domain

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The induced signal from the patient decreases with time as the proton spins relax

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The time between the initial 90 degree pulse and the Peak signal is called

A

TE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

The time from the initial 90 degree RF pulse to the next RF pulse is termed?

A

repition time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In phase is also called?

A

coherent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Phase is measured in____________

A

radians of degrees

23
Q

—Frequency is the unit of occurrence or frequency and is measured as Hertz (Hz).

A

true

24
Q

Hydrogen Nuclei start to Recover back to Bo or the Longitudinal Plane, they are now Out of Phase

A

true

25
Q

—T1 recovery(spin lattice relaxation) is the relaxation time for 67% of the Net magnetization of the tissue to recover.

A

false

26
Q

—The T2 relaxation time is the time it takes for tissue to decay in the transverse plane to 37% (or 63% to be lost)

A

true

27
Q

The time from the initial 90 degree RF pulse to the next RF pulse is termed?

A

repition time

28
Q

Know as the father of MRI

A

felix bloch

29
Q

When the protons return to their “normal” state in the longitudinal plane (Z) after being excited by the RF pulse this is called.

A

equilibrium

30
Q

The 90 degree RF pulse is also called the ______________.

A

flip angle

31
Q

Number of Protons in the Nucleus is termed.

A

Atomic Number

32
Q

In the presence of a Magnetic Field a spinning proton

A

precesses

33
Q

At 1 Tesla the gyromagnetic ratio of hydrogen is

A

42.57 Mhz

34
Q

A Vector is a quantity that has

A

magnitude and direction

35
Q

When a patient is subjected to a strong magnetic field the patient becomes polarized and has

A

Net Magnetization

36
Q

Precession Frequency depends on what factor(s)

A

Type of atoms nucleus.

Strength of Bo

37
Q

Who is considered by most to be the father of MRI

A

Felix Bloch

38
Q

Once the Hydrogen nuclei are subjected to a external magnetic field they start to__________.

A

Wobble

Line up with or against the field

Precess

39
Q

A Magnetic Field is created when (select two)

A

A charged particle moves

Current is moving along a path of wire

40
Q

Hydrogen contains its own large magnetic moment due to the odd number of Protons in the Nucleus

A

True

41
Q

With no exposure to a Magnetic Field, Magnetic moments are randomly situated

A

True

42
Q

Once a Magnetic Moment is exposed to an external Magnetic Field it will line up with or against the external field.

A

True

43
Q

Spin up Nuclei contain energy that are

A

low

44
Q

Spin down Nuclei contain energy that is

A

high

45
Q

Net Magnetization Vector (N.M.V.) is the result of

A

A battle between Spin Up and Spin Down Nuclei

46
Q

In order for resonance to occur the RF Pulse needs to match the exact precessional Frequency of Hydrogen Atoms

A

True

47
Q

Once a Magnetic Moment is exposed to an external Magnetic Field it will line up with or against the external field.

A

true

48
Q

This signal is the intial signal recieved after the 90 degree excitation pulse.

A

FID

49
Q

When Hydrogen Atoms are termed In Phase it refers to the precessing magnetic moments being

A

On the same point in their Precessional Path

50
Q

In order for resonance to occur the RF Pulse needs to match the exact precessional Frequency of Hydrogen Atoms

A

True

51
Q

Precessional Frequency of any atom that meets the criteria for MRI, we must know what two things.

A

The gyro magnetic ratio of that atom at 1 T

Strength of Bo

52
Q

The F.I.D. can be defined as

A

Signal after the R.F. pulse is removed

Primary signal

Dephasing Hydrogen Protons

53
Q

Once the RF pulse is removed Mo realigns to Bo and creates magentization decays

A

True

Z MRI Physics (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions